CrystalDiskMark vs AS SSD Benchmark: Which Speed Test is Better? (2026 Guide)

CrystalDiskMark vs AS SSD Benchmark: We compare the two most popular free SSD testing tools. Learn the difference between compressible data, copy tests, and which benchmark you should trust.

Introduction

If you want to know exactly how fast your new Solid State Drive (SSD) is, you will inevitably run into two legendary pieces of freeware: CrystalDiskMark and AS SSD Benchmark.

On the surface, they look incredibly similar. They both feature a simple grid interface, they both test Sequential and Random read/write speeds, and they both output results in Megabytes per second (MB/s).

However, beneath the surface, these two programs test your hardware in entirely different ways. Depending on the type of SSD controller you have, one program might show a blazing-fast score of 7,000 MB/s, while the other shows a much slower 5,000 MB/s on the exact same drive!

In this comprehensive guide, we will break down the exact differences in the CrystalDiskMark vs AS SSD Benchmark showdown, explain why their scores differ, and help you decide which tool to trust.

CrystalDiskMark: The Industry Standard

Developed in Japan by Crystal Dew World, CrystalDiskMark (CDM) is the most widely recognized storage benchmark on the internet. Whenever a manufacturer like Samsung or Western Digital advertises the “up to” speeds on their SSD boxes, they are almost always quoting a CrystalDiskMark result.

How it Works: CrystalDiskMark tests your drive’s peak, absolute maximum performance capabilities. It highly stresses the drive by simulating different “Queue Depths” (how many data requests are waiting in line) and “Threads” (how many software processes are asking for data at once).

The Pros:

• Highly Customizable: You can adjust the test file size (from 16MB to 64GB), the queue depth, and the thread count to perfectly simulate your specific workload.

• Peak Performance: It shows you the absolute maximum speed your drive is capable of achieving under ideal conditions.

• Modern NVMe Profile: The newest versions include a specific “NVMe SSD” profile designed to push PCIe Gen 4 and Gen 5 drives to their absolute limits.

The Cons:

• Unrealistic Expectations: Because it tests for absolute peak performance, the speeds you see in CrystalDiskMark are rarely the speeds you will experience in normal, daily Windows usage.

AS SSD Benchmark: The Worst-Case Scenario Tester

Developed in Germany, AS SSD Benchmark was created specifically to expose the weaknesses in early SSD controllers (specifically SandForce controllers, which used data compression to cheat speed tests).

How it Works:

Unlike other testers, AS SSD uses 100% incompressible data (completely randomized zeros and ones). It forces the SSD controller to work as hard as physically possible without using any software shortcuts or caching tricks.

The Pros:

• The “Copy Benchmark”: This is AS SSD’s secret weapon. Instead of just showing raw MB/s, it includes a real-world copy test. It simulates exactly how long it will take (in seconds) to copy an ISO file, load a heavy software Program, or launch a Game.

• The Overall Score: At the end of the test, AS SSD gives you a single, unified “Score” (e.g., 5,200). This makes it incredibly easy to compare two completely different drives without having to analyze eight different data points.

• Shows True Minimum Speeds: Because it uses incompressible data, AS SSD shows you the “worst-case scenario” for your drive.

The Cons:

• Lower Scores: Your speeds will almost always look slower in AS SSD compared to CrystalDiskMark. This can confuse users into thinking their drive is broken.

• Outdated UI: The software has not been updated as frequently as CrystalDiskMark, and the interface feels quite old.

The Core Difference: Compressible vs Incompressible Data

If you run both tests back-to-back, you will notice something strange: CrystalDiskMark will usually give you a higher score. Why?

It comes down to how the data is generated.

• Some SSD controllers use a trick where they instantly compress data on the fly to write it faster.

• By default, CrystalDiskMark generates data that is fairly easy for the SSD to compress, allowing the drive to hit its absolute maximum advertised speeds.

• AS SSD Benchmark intentionally generates data that is mathematically impossible to compress. This forces the SSD to write the full weight of the file, completely bypassing the controller’s speed tricks.

Think of CrystalDiskMark as testing a car’s top speed on a perfectly smooth racetrack, while AS SSD Benchmark tests that same car’s speed while driving up a steep, muddy hill.

Feature Comparison Table

Feature	CrystalDiskMark	AS SSD Benchmark
Data Type Used	Default (Customizable)	100% Incompressible
Real-World “Copy” Test	No	Yes (ISO, Program, Game)
Overall Final Score	No	Yes
Customizable Queue Depths	Yes (Highly advanced)	Limited
Best For	Finding absolute peak speeds	Finding worst-case scenario speeds

Conclusion: Which One Should You Use? 

At the end of the day, both tools are completely free, lightweight, and safe to use. You do not have to pick just one!

• Use CrystalDiskMark when you install a brand-new drive and want to verify that it hits the speeds printed on the manufacturer’s box. It is the gold standard for verifying that your hardware is working correctly.

• Use AS SSD Benchmark when you want to know exactly how your drive will perform under the heaviest, most unoptimized workloads, or if you want a simple “Overall Score” to compare against your friend’s PC.

CrystalDiskInfo Not Detecting Your Drive? (5 Easy Fixes)

Is CrystalDiskInfo not showing your external hard drive, USB, or internal SSD? Try these 5 simple fixes to resolve the “Disk Not Found” error and read your S.M.A.R.T. data.

Introduction

You suspect your hard drive might be failing, so you download CrystalDiskInfo to check its health. But when you open the software, your drive is completely missing from the top menu bar.

Seeing a blank screen or a “Disk Not Found” error in CrystalDiskInfo is incredibly frustrating. However, before you panic and assume your drive is completely dead, you should know that this is a very common software issue.

CrystalDiskInfo requires low-level hardware access to read S.M.A.R.T. data. Sometimes, Windows permissions, cheap USB enclosures, or outdated software can block this connection. Here are 5 easy ways to fix CrystalDiskInfo not detecting your drive.

Fix 1: Enable Advanced USB Search (For External Drives)

By far, the most common reason CrystalDiskInfo cannot see a drive is because it is plugged in externally via USB. Many external hard drive enclosures use cheap “bridge chips” that block S.M.A.R.T. data from reaching the computer.

Furthermore, CrystalDiskInfo occasionally ignores USB drives by default to speed up its loading time. You need to force the software to look for them.

How to fix it:

1. Open CrystalDiskInfo.

2. Click on Function in the top menu bar.

3. Hover over Advanced Feature.

4. Click on Advanced Disk Search.

5. (Optional) If it still doesn’t appear, go back to Advanced Feature and click on [DEBUG] USB/IEEE 1394.

Note: CrystalDiskInfo is designed for HDDs and SSDs. It generally cannot read standard USB Flash Drives (thumb drives) or SD cards, as those devices do not have S.M.A.R.T. monitoring chips built into them.

Fix 2: Run as Administrator

To talk directly to your motherboard and storage controllers, CrystalDiskInfo needs elevated Windows permissions. If you are running the program on a standard Windows user account without Admin rights, the software will be blocked from seeing your drives.

How to fix it:

1. Close CrystalDiskInfo completely.

2. Right-click on the CrystalDiskInfo shortcut (or the .exe file).

3. Select “Run as Administrator.”

4. Click “Yes” on the Windows User Account Control prompt.

Fix 3: Update to the Latest Version

Storage technology changes rapidly. If you are using a brand-new PCIe Gen 5 NVMe SSD, or a newly released external NVMe-to-USB enclosure, an older version of CrystalDiskInfo simply might not have the code required to recognize the new controller.

How to fix it: If you are running version 8.0 or older, it is time to upgrade. Head back to the CrystalMarkInfo homepage and download the latest version (v9.0+). Installing the newest version directly over your old one often fixes missing NVMe and external drive bugs instantly.

Fix 4: The RAID Array Limitation

Are you running two or more drives tied together in a RAID array (like RAID 0 for speed or RAID 1 for redundancy)?

The Hard Truth: CrystalDiskInfo does not support most hardware RAID controllers. When drives are put into a hardware RAID, the controller chip acts as a middleman and hides the individual S.M.A.R.T. data of the drives from Windows.

How to fix it: If you need to check the health of a drive inside a hardware RAID, you will either need to use the proprietary software provided by your RAID controller manufacturer (like Intel Rapid Storage Technology or AMD RAIDXpert), or you must temporarily remove the drive and plug it directly into a standard SATA port on your motherboard.

Fix 5: Check Windows Disk Management

If you have tried all the steps above and CrystalDiskInfo still cannot see your drive, we need to find out if Windows can even see it.

How to fix it:

1. Right-click on the Windows Start Button.

2. Select Disk Management from the menu.

3. Look through the list of drives at the bottom of the window.

• If you see the drive here (even if it says “Unallocated” or “RAW”): Your drive is physically alive, but the partition is corrupted. You can try recovering data with software like DMDE or Recuva.

• If the drive is completely missing from Disk Management: The drive is physically disconnected or dead. Check your SATA cables, try a different M.2 slot, or try a different USB cable. If it still doesn’t show up in Disk Management, the drive has suffered a fatal hardware failure and needs to be replaced.

Summary

CrystalDiskInfo is a powerful tool, but it relies on clear communication pathways to your hardware. By running the software as an Administrator,

What is a Good CrystalDiskMark Score for Your SSD? (2026 Guide)

Wondering what a good CrystalDiskMark score is? We break down SEQ1M vs RND4K speeds and provide average benchmark ranges for HDDs, SATA SSDs, and NVMe drives.

Introduction

You just built a new PC or bought a high-end SSD, installed it, and immediately downloaded CrystalDiskMark to test its speed. You click “All” to run the benchmark, and a few minutes later, you are staring at a grid of massive numbers.

While seeing a score of 7,000 MB/s looks incredibly impressive, most users have no idea what these numbers actually mean or if their drive is performing the way it should. What exactly is a good CrystalDiskMark score?

In this comprehensive guide, we will break down exactly how to read your benchmark results, explain the critical difference between Sequential and Random speeds, and give you the average score ranges for every type of drive on the market today.

Understanding the Tests: Sequential vs. Random

CrystalDiskMark doesn’t just run one test; it simulates different ways your computer actually uses data. To understand your score, you must understand the two main rows on the results screen: SEQ1M and RND4K.

SEQ1M Q8T1 (Sequential Large File Transfers)

The top rows of your benchmark represent Sequential read and write speeds. This tests how fast your drive can move a single, massive file in one continuous block.

• Real-World Example: Copying a massive 50GB 4K movie file from one folder to another, or downloading a massive zipped game file.

• The Marketing Metric: When you look at an SSD box and it proudly claims “Speeds up to 7,400 MB/s,” they are advertising the Sequential speed. It looks great on paper, but it is not how your computer operates most of the time.

RND4K Q32T1 (Random Tiny Files)

The bottom rows represent Random 4K read and write speeds. This tests how fast your drive can find and move thousands of tiny, scattered files located all over the storage chips.

• Real-World Example: Booting up Windows, launching your web browser, or loading a game with thousands of small texture files.

• The “Feel” Metric: This is the most important score for a snappy, responsive PC. Even the fastest Gen 5 NVMe drives will score dramatically lower here (often under 100 MB/s), but this is the number that dictates how fast your computer actually feels during everyday tasks.

What is a Good CrystalDiskMark Score?

A “good” score depends entirely on the physical hardware you have installed. You cannot compare an old mechanical hard drive to a modern M.2 stick.

Here are the target Sequential (SEQ1M) speed ranges you should expect depending on your storage type:

Drive Type	Expected Read Speed (MB/s)	Expected Write Speed (MB/s)	Best Used For
Traditional SATA HDD	100 to 250	100 to 200	Mass storage, backups, archives
SATA 2.5″ SSD	500 to 550	450 to 530	Older laptops, budget game drives
Gen 3 NVMe M.2 SSD	3,000 to 3,500	2,500 to 3,300	Excellent everyday performance
Gen 4 NVMe M.2 SSD	5,000 to 7,500	4,000 to 6,800	High-end gaming, video editing
Gen 5 NVMe M.2 SSD	10,000 to 14,000+	9,000 to 12,000+	Extreme enthusiast workloads

Why is My Score Lower Than the Box Says?

If you bought a Gen 4 NVMe SSD advertised at 7,000 MB/s, but CrystalDiskMark is only showing a score of 3,500 MB/s or less, do not panic. Your drive is likely fine, but it is being limited by one of these common bottlenecks:

• Motherboard Bottlenecks (PCIe Generations): This is the most common issue. If you plug an ultra-fast Gen 4 SSD into an older motherboard that only supports PCIe Gen 3, the motherboard will limit the drive to Gen 3 speeds (capping it around 3,500 MB/s).

• Testing Your Boot Drive: If you are benchmarking the exact same drive that Windows is currently running on, your scores will be lower. Windows is constantly reading and writing background files, which interrupts the CrystalDiskMark test.

• Thermal Throttling: NVMe SSDs get incredibly hot. If your drive does not have a heatsink, it might hit 70°C+ during the benchmark and intentionally slow itself down to prevent melting.

• “Up To” Marketing Speeds: Manufacturers test their drives in absolutely perfect, laboratory conditions on completely empty drives. A drive that is 80% full will naturally benchmark slightly slower than an empty one.

The Bottom Line

When trying to determine what a good CrystalDiskMark score is, always manage your expectations based on your hardware. If your Sequential speeds are near the advertised limits of your drive’s generation, your hardware is perfectly healthy.

However, remember not to obsess over the massive 7,000+ MB/s sequential numbers. If your computer boots up instantly and applications open without delay, your Random 4K speeds are doing exactly what they need to do.

CrystalDiskInfo vs Hard Disk Sentinel: Which Drive Monitor is Better?

Deciding between CrystalDiskInfo and Hard Disk Sentinel? We compare the free, easy-to-use S.M.A.R.T. reader against the paid, deep-diagnostic tool to help you choose.

Introduction

When it comes to monitoring the health of your Hard Disk Drives (HDDs) and Solid State Drives (SSDs), two names dominate the conversation: CrystalDiskInfo and Hard Disk Sentinel (HDSentinel).

If you are trying to figure out which one to download, you aren’t alone. Both tools are highly respected in the PC building and data recovery communities. However, they are built for entirely different types of users. One is a lightweight, free snapshot of your drive’s health, while the other is a premium, deep-diagnostic suite designed to predict failures before they happen.

In this guide, we will compare CrystalDiskInfo vs. Hard Disk Sentinel to help you decide which storage monitor is the right fit for your computer.

CrystalDiskInfo: The Casual Health Checker 

CrystalDiskInfo is the undisputed king of freeware drive monitoring. It is a lightweight, open-source tool designed to do one thing very well: read your drive’s internal S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data and translate it into a simple, color-coded health grade.

The Pros:

• 100% Free: There are no premium tiers or locked features.

• Incredibly Simple: You launch it, and instantly see a “Good,” “Caution,” or “Bad” status.

• Lightweight: It uses practically zero system resources, meaning you can leave it running in the background while gaming or working.

• Temperature Monitoring: Displays real-time temperatures on your Windows taskbar.

The Cons:

• Passive Monitoring Only: It only reads what the drive tells it. It cannot actively scan the physical surface of the drive for hidden errors.

• Limited Hardware Support: It struggles to read drives configured in complex RAID arrays or NAS (Network Attached Storage) setups.

Who is it for? CrystalDiskInfo is perfect for 90% of casual PC users and gamers. If you just want a quick, free way to make sure your brand-new SSD is healthy or to check why your old laptop is running slow, this is the only tool you need.

Hard Disk Sentinel: The Deep-Dive Doctor

Hard Disk Sentinel (often abbreviated as HDS) is a premium, professional-grade diagnostic tool. While CrystalDiskInfo simply reads the drive’s self-reported log, Hard Disk Sentinel actively interrogates the hardware.

The Pros:

• Active Surface Testing: HDSentinel can run intense read/write hardware tests to physically verify every single sector on the drive. It can sometimes even force a dying drive to reallocate bad sectors, stabilizing it temporarily.

• Failure Prediction: It doesn’t just tell you if a drive is bad; it calculates an estimated “Days Remaining” before the drive completely dies.

• Advanced Alerts: It can be configured to automatically send you an email or shut down your PC entirely if a drive crosses a dangerous temperature threshold.

• Broad Support: It flawlessly reads drives in RAID arrays, external USB enclosures, and complex server setups.

The Cons:

• It Costs Money: While there is a limited free trial, the Pro version requires a paid license (typically around $30-$50).

• Overwhelming Interface: The sheer amount of data, graphs, and textual descriptions can be intimidating for beginners.

Who is it for?

Hard Disk Sentinel is built for IT professionals, server admins, and data hoarders. If you have a NAS filled with 80TB of irreplaceable family videos, or if you run a small business server, the investment in Hard Disk Sentinel is absolutely worth the peace of mind.

Side-by-Side Feature Comparison

Feature	CrystalDiskInfo	Hard Disk Sentinel (Pro)
Price	Free	Paid (Lifetime License)
S.M.A.R.T. Reading	Yes	Yes
Temperature Monitoring	Yes	Yes
Hardware Surface Tests	No	Yes
Predicts Lifespan (Days)	No	Yes
RAID / NAS Support	Limited	Comprehensive
Automated Backups on Alert	No	Yes

 

Conclusion: Which One Should You Download?

Choosing between CrystalDiskInfo and Hard Disk Sentinel comes down to what you are trying to protect and your budget.

If you are a standard home user, gamer, or student with a single PC, CrystalDiskInfo is the clear winner. It gives you all the essential warnings you need for exactly zero dollars.

However, if you are managing a server, working with multi-drive RAID setups, or trying to diagnose a highly corrupted hard drive that Windows refuses to read, you need the heavy-duty active testing that Hard Disk Sentinel provides.

Pro Tip: You don’t have to choose permanently! Many PC builders keep CrystalDiskInfo installed for daily background monitoring, and only download the Hard Disk Sentinel trial when they suspect a severe hardware issue.

Why Your SSD Health Percentage is Dropping in CrystalDiskInfo (TBW Explained)

Worried about your SSD health dropping to 99% or lower in CrystalDiskInfo? Learn what Terabytes Written (TBW) means, why this is completely normal wear-and-tear, and when you should actually panic.

Introduction

You just built a new PC, or maybe you just downloaded CrystalDiskInfo to check on your laptop’s storage. You open the program, expecting to see a perfect 100% health score, but instead, your Solid State Drive (SSD) says 99%, 95%, or even 80% Good.

For many users, watching that health percentage tick down creates instant anxiety. Is the drive failing? Do you need to buy a new one? Did you do something wrong?

Take a deep breath. In the vast majority of cases, an SSD health percentage dropping in CrystalDiskInfo is completely normal and expected. In this guide, we are going to explain exactly how SSDs age, what Terabytes Written (TBW) means, and the critical difference between normal SSD wear-and-tear and dangerous Hard Drive (HDD) failures.

The Secret to SSDs: They Are Basically Erasers

To understand why your health is dropping, you have to understand how an SSD works.

Unlike traditional mechanical hard drives (HDDs) that use spinning magnetic platters and a physical needle to write data, SSDs use flash memory cells. You can think of these flash memory cells like a piece of paper and a pencil eraser.

Every time you save a file, download a game, or install a Windows update, the SSD “writes” to a cell. When you delete a file to make room for something else, the SSD has to “erase” that cell before it can write to it again.

Here is the catch: A flash memory cell can only be written to and erased a specific number of times before it wears out completely. This is called the Program/Erase (P/E) cycle.

What is TBW (Terabytes Written)?

Because flash memory degrades slightly with every write, SSD manufacturers give their drives an endurance rating called TBW (Terabytes Written).

TBW is the total amount of data you can write to the SSD before the manufacturer considers the warranty void and the drive begins to run out of usable memory cells.

• Example: If you buy a 1TB Samsung 980 Pro, it has an endurance rating of 600 TBW. That means you can write 600 Terabytes of data to it before it theoretically exhausts its lifespan.

When CrystalDiskInfo shows your SSD health dropping from 100% to 99%, it is simply acting as a fuel gauge. It is looking at the total TBW rating of your drive, looking at how much data you have written so far, and doing the math.

A drop to 99% just means you have used up 1% of your drive’s total guaranteed lifespan. It is not an error; it is a progress bar.

SSD Normal Wear vs. HDD Bad Sectors (The Crucial Difference)

This is where most of the confusion happens. Users see an SSD at 95% and panic, assuming it is the same as an old hard drive failing. They are not the same.

The SSD Scenario (Normal Wear)

If your SSD is at 95% Health and the status is still Blue/Green (Good), your drive is perfectly fine. It is just aging gracefully. A drive at 80% health operates exactly as fast and as safely as a drive at 100% health. It just has fewer miles left on the tires.

The HDD Scenario (Hardware Damage)

If you have a traditional mechanical Hard Disk Drive (HDD) and CrystalDiskInfo shows a yellow Caution status, this is an entirely different story. HDDs do not have a “health percentage” based on TBW. If an HDD shows a warning, it means physical sectors on the magnetic disk have violently crashed and died (Reallocated Sectors).

• To summarize: An SSD dropping to 90% is just tracking normal usage. An HDD triggering a “Caution” alert means physical hardware damage has occurred, and the drive is actively dying.

How to Check Your Total Data Written

Curious exactly how much data you have blasted through your SSD? CrystalDiskInfo tells you this right on the main screen!

1. Open CrystalDiskInfo.

2. Look at the top right corner of the window.

3. Find the box labeled Total Host Writes.

This box will tell you exactly how many Gigabytes (GB) or Terabytes (TB) of data your computer has written to that drive since the day it was manufactured. If you do heavy video editing or constantly uninstall and reinstall massive 100GB+ games, this number will climb quickly (and your health percentage will drop to match it).

When Should You Actually Worry About Your SSD?

While a slowly dropping percentage is normal, there are a few scenarios where you should take immediate action:

• The Free-Fall: If your SSD health was 100% yesterday, and it is 80% today, something is wrong. An incredibly fast drop means a program is continuously writing background data (a runaway process), or the SSD controller is failing.

• The “Bad” Status: If your SSD drops all the way to 0% health, or the CrystalDiskInfo status turns Red (Bad), the drive has exhausted its flash memory cells.

• Read-Only Mode: When modern SSDs realize they are about to die, they often lock themselves into “Read-Only” mode. This means you can copy your files off the drive to save them, but you cannot save any new files, and Windows will crash if it tries to update. If this happens, your drive is done.

Conclusion

Seeing your brand-new SSD drop to 99% health in CrystalDiskInfo can be startling, but it is just the reality of how flash memory works. As long as the status says “Good,” you have nothing to worry about.

Just keep an eye on your Total Host Writes, avoid running unnecessary daily speed benchmarks (like CrystalDiskMark!), and your SSD will likely outlast the rest of the components in your PC.

Standard vs Shizuku vs Aoi: Which CrystalDiskInfo Edition Should You Download?

If you want to check the health of your hard drive or SSD, CrystalDiskInfo is the absolute gold standard. But when you land on the official download page, you’re immediately faced with a confusing choice: should you download the Standard, Shizuku, Aoi, or Kurei Kei edition?

If you’re scratching your head over the CrystalDiskInfo Shizuku vs Standard debate, you aren’t alone. It’s one of the most common points of confusion for new users. Let’s break down exactly what these versions are, how they differ, and which one you should click download on.

The Short Answer: They Are Exactly the Same Under the Hood

Let’s clear up the biggest misconception right away: Every single edition of CrystalDiskInfo functions identically. Whether you download the barebones Standard edition or one of the colorful anime versions, you are getting the exact same diagnostic tool. They all read the same S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data, monitor your drive temperatures, and warn you of impending hardware failures with the exact same accuracy.

The differences between the versions are 100% cosmetic.

The Standard Edition: Best for Normal Users

For the vast majority of people—especially if you’re fixing a family member’s PC, working in a professional IT environment, or just want a quick diagnostic check—the Standard Edition is what you need.

• Clean Interface: It features a straightforward, no-nonsense UI that displays your drive data clearly and professionally.

• Small File Size: Because it doesn’t include massive audio or image assets, the download is incredibly lightweight and installs in seconds.

• What to click: On the download page, look for the Standard Edition. We recommend downloading the Installer (EXE) version, as it is the easiest to set up and get running immediately.

Shizuku, Aoi, and Kurei Kei Editions: The Anime Experience

So, what are all these other versions? Over the years, the developer of CrystalDiskInfo created official anime mascots for the software to add a bit of fun to an otherwise dry utility.

• Shizuku Edition: Features Suisho Shizuku, the original and most famous mascot. The interface is heavily themed with her artwork.

• Aoi Edition: Features a secondary mascot character, Aoi.

• Kurei Kei Edition: A special collaboration featuring a popular Japanese IT mascot named Kurei Kei.

What makes them different?

• Anime Themes: The backgrounds, buttons, and overall UI are replaced with high-quality anime illustrations.

• Voice Alerts: This is the biggest feature. If your drive gets too hot or encounters a critical error, these editions will actually speak to you in Japanese to warn you, fully voiced by professional voice actresses.

• Larger File Size: Because of the high-resolution art and uncompressed audio files, these downloads are significantly larger (often hundreds of megabytes compared to the Standard edition’s few megabytes).

When it comes to CrystalDiskInfo Shizuku vs Standard, the choice comes down entirely to your personal preference for your desktop aesthetic.

If you just want to quickly check your SSD’s health, read your data, and move on with your day, download the Standard Edition (EXE). It is the practical choice for almost everyone.

However, if you are an anime fan, love customizing your PC with unique themes, and think it would be fun to have a Japanese voice actress yell at you when your hard drive overheats, feel free to grab the Shizuku, Aoi, or Kurei Kei editions! They are entirely safe, officially supported, and a genuinely unique piece of software history.

CrystalDiskInfo vs CrystalDiskMark: What’s the Difference? (2026 Guide)

 

Confused about CrystalDiskInfo vs CrystalDiskMark? We break down the exact differences between these two essential PC tools, what they do, and which one you actually need to download.

Introduction

If you are looking to check up on your computer’s storage drive, you have probably come across the name “Crystal Dew World” and its two most famous tools: CrystalDiskInfo and CrystalDiskMark.

Because the names are nearly identical, thousands of users download the wrong software every day. While both are completely free, incredibly useful, and created by the same developer, they do two totally different jobs.

To put it simply: One is a doctor, and the other is a stopwatch.

In this guide, we will explain the exact differences between CrystalDiskInfo and CrystalDiskMark, what each tool is used for, and which one you need for your PC.

What is CrystalDiskInfo? (The Health Monitor)

CrystalDiskInfo is a diagnostic and health-monitoring tool. Think of it as a medical check-up for your Hard Disk Drive (HDD) or Solid State Drive (SSD).

It does not test how fast your drive is. Instead, it reads the internal log files of your drive (called S.M.A.R.T. data) to tell you if the hardware is healthy, dying, or already failing.

Key Features of CrystalDiskInfo:

• Overall Health Status: Gives you a simple color-coded grade (Good, Caution, or Bad).

• Temperature Monitoring: Shows you exactly how hot your drive is running in real-time.

• Error Reporting: Tracks hardware degradation, such as Reallocated Sectors or Uncorrectable Errors.

• Drive Details: Shows you the firmware version, serial number, total power-on hours, and total data written over the drive’s lifespan.

When to use it: You should use CrystalDiskInfo if your computer is crashing, freezing, showing the “Blue Screen of Death” (BSOD), or if you just bought a used drive and want to make sure it isn’t broken.

What is CrystalDiskMark? (The Speed Benchmark)

CrystalDiskMark is a performance benchmarking tool. Think of it as a racetrack for your storage. It does not care if your drive is healthy or dying; it only cares about how fast it can move data.

When you click “Start” in CrystalDiskMark, the software actively creates massive dummy files and forces your drive to read and write them as fast as possible. It then gives you a score in Megabytes per second (MB/s).

Key Features of CrystalDiskMark:

• Sequential Testing: Measures how fast your drive can read/write single, massive files (like a 50GB 4K video).

• Random Testing (RND4K): Measures how fast your drive can read/write thousands of tiny, scattered files (which is crucial for your Windows operating system speed).

• Customizable Workloads: Lets you adjust the file sizes and test passes to push your hardware to the absolute limit.

When to use it: You should use CrystalDiskMark when you install a brand-new NVMe SSD and want to verify it actually hits the 7,000 MB/s speed printed on the box, or if you are a tech reviewer comparing two different brands of storage.

Side-by-Side Comparison

Feature	CrystalDiskInfo	CrystalDiskMark
Primary Purpose	Health & Diagnostics	Speed Benchmarking
Reads S.M.A.R.T. Data	Yes	No
Measures Read/Write Speed	No	Yes
Monitors Temperature	Yes	No
Writes Data to Drive	No (Read-Only)	Yes (Heavy data writing)
Best For	Troubleshooting crashes	Testing new hardware

 

Warning: Can Using These Tools Damage My Drive?

It is important to know how these tools interact with your hardware.

CrystalDiskInfo is 100% safe to leave running. Because it only reads text data that your drive is already reporting, it causes zero wear and tear. You can leave it open in the background 24/7 to monitor your temperatures.

CrystalDiskMark causes slight wear and tear. Solid State Drives (SSDs) have a limited lifespan based on how much data is written to them over their lifetime (known as Terabytes Written, or TBW). Because CrystalDiskMark works by writing dozens of Gigabytes of dummy data to your drive to test its speed, running it constantly will slowly degrade your SSD. Running it once or twice when you build a new PC is perfectly fine, but you should not run speed benchmarks every day.

Conclusion: Which One Should You Download?

• Download CrystalDiskInfo if you are worried about your PC’s health, your computer is acting sluggish, or you want to make sure your data is safe from hardware failure.

• Download CrystalDiskMark if you are an enthusiast who wants to test the maximum speed limits of your newly purchased gaming SSD.

For most standard users, CrystalDiskInfo is the essential tool to keep installed on your machine.

Is CrystalDiskInfo Safe? (Malware, Adware & False Positives Explained)

If you’ve noticed your computer slowing down, freezing, or making strange clicking noises, someone on the internet has probably told you to download CrystalDiskInfo. It is the gold standard for checking the health of your hard drives and Solid State Drives (SSDs). But before you click that download button, a very reasonable question pops up: Is CrystalDiskInfo actually safe?

The short answer is a resounding yes—but with a few important caveats regarding how and where you get it.

Let’s break down everything you need to know about this popular tool, including why your antivirus might be throwing a fit.

The Official Software is 100% Safe (And Open-Source)

When downloaded from the official source, CrystalDiskInfo is entirely safe, legitimate, and free of malware.

Created by a Japanese developer known as hiyohiyo, the program has been a trusted industry standard for over a decade. It works by reading your drive’s S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data. This translates the complex raw data inside your drive into an easy-to-read dashboard, telling you critical information like the drive’s temperature, how many hours it has been running, and most importantly, if any sectors are actively failing.

Furthermore, it is open-source software. This means the underlying code is publicly available for anyone to inspect. Cybersecurity experts and developers worldwide regularly review it, ensuring there are no hidden keyloggers, spyware, or malicious scripts baked into the official program.

The Danger Zone: Third-Party Downloads and Adware

If the software is so safe, why do people sometimes get viruses when installing it? The problem isn’t the software itself; it’s where they downloaded it.

Because CrystalDiskInfo is incredibly popular and free, shady third-party software hosting sites love to re-package it. If you download the tool from a random tech blog, a torrent, or an unverified software repository, you run a high risk of downloading a modified, malicious installer.

These fake installers often bundle:

• Adware: Annoying pop-ups, browser hijackers, and toolbars that change your default search engine.

• Bloatware: Unwanted “system optimizers” or fake antivirus trials that bog down your PC.

• Malware: In worst-case scenarios, actual viruses and ransomware.

How to stay safe: Only download CrystalDiskInfo from the official developer’s website (Crystal Dew World) or their official SourceForge/GitHub repositories.

(Note: The official site offers a few different visual themes, including the “Shizuku Edition,” which features anime-style artwork. These anime versions are completely official and safe, though they sometimes confuse first-time users!)

Why Did My Antivirus Flag It? (The False Positive Dilemma)

So, you went to the official site, downloaded the clean version, and suddenly Windows Defender or Malwarebytes throws up a giant red warning. What gives?

This is what the cybersecurity world calls a false positive. Here is exactly why it happens:

1. Low-Level Hardware Access: To get accurate S.M.A.R.T. data, CrystalDiskInfo has to bypass the standard operating system layers and talk directly to your hard drive’s micro-controller.

2. Suspicious Behavior Patterns: Most standard programs (like your web browser or video games) never need this kind of deep, low-level hardware access. You know what does request that kind of access? Rootkits and severe malware.

3. Heuristic Scanning: Modern antivirus software looks for “suspicious behavior,” not just known virus signatures. Because CrystalDiskInfo pokes around in the deepest, most sensitive parts of your hardware, overly aggressive antivirus heuristics sometimes panic and flag it as a threat.

As long as you are 100% certain you downloaded the installer from the official source, you can safely tell your antivirus to ignore the warning and whitelist the program.

The Final

CrystalDiskInfo is an essential, perfectly safe tool for diagnosing failing hard drives and preventing catastrophic data loss. The software itself is not malware, and it will not harm your computer. Just be a smart surfer: stick to the official website and don’t let overly cautious antivirus warnings scare you away from keeping your hardware healthy.

What Does “Caution” Mean in CrystalDiskInfo? (Complete Guide)

Seeing a yellow “Caution” health status in CrystalDiskInfo? Learn exactly what triggers this warning, which S.M.A.R.T. values to check, and how to save your data before your drive fails.

If you recently downloaded CrystalDiskInfo to check up on your PC and were immediately greeted by a bright yellow “Caution” badge, you are likely feeling a bit of panic. Hard drives and SSDs hold our most important files, photos, and projects, and seeing a warning about their health is never a good feeling.

But take a deep breath. A “Caution” status does not mean your hard drive will explode in the next five minutes. However, it is a serious warning light on your computer’s dashboard.

In this comprehensive guide, we will explain exactly why CrystalDiskInfo is showing you this warning, how to identify the specific problem, and the exact steps you need to take right now to protect your data.

What Triggers the “Caution” Status?
To understand the warning, you need to understand how CrystalDiskInfo works. The software doesn’t actually test your drive; instead, it reads a log file that your drive creates about itself. This log is called S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology).

Every modern Hard Disk Drive (HDD) and solid-state drive (SSD) has S.M.A.R.T. built in. The drive constantly monitors its own physical health, tracking everything from temperature to read/write errors.

CrystalDiskInfo triggers the yellow “Caution” status when one or more of your drive’s S.M.A.R.T. attributes drop below a safe threshold established by the manufacturer. It means your drive has detected physical degradation.

The 3 Critical S.M.A.R.T. Values (The Culprits)
When you see the Caution badge, look at the bottom half of the CrystalDiskInfo window. You will see a long list of attributes. One or more of these will have a yellow dot next to them.

In 99% of cases, the Caution status is triggered by one of these three specific errors:

1. Reallocated Sectors Count
Think of your hard drive’s storage space like a massive parking lot, and your data is the cars. A “sector” is a single parking spot.

When a sector physically breaks and can no longer hold data, the drive’s internal controller notices. It takes the data from that broken spot and moves it to a secret, reserved backup sector (a “spare tire” parking spot). This is called a reallocation.

What it means: If this number is greater than zero, your drive is physically breaking down. It is using up its backup sectors. Once the backup sectors are gone, any new broken sectors will result in permanent data loss.

2. Current Pending Sector Count
This is the “investigation” phase. A pending sector is a spot on the drive that the computer tried to read, but failed.

The drive marks this sector as “pending.” It is waiting for you to try and write new data to that exact spot. If the new data writes successfully, the drive removes the warning. If it fails again, it officially declares the sector dead and moves it to the “Reallocated” list (Attribute [05]).

What it means: High pending sector counts often cause your computer to freeze, crash, or give you the “Blue Screen of Death” (BSOD) because Windows is trying and failing to read critical files.

3. Uncorrectable Sector Count
This is the most severe of the three warnings. An uncorrectable sector means that a physical area of the drive has completely failed, and the data that was stored there could not be recovered or moved to a backup sector.

What it means: Data loss has already occurred. A file, a piece of a program, or part of your operating system is permanently gone or corrupted.

Is My Hard Drive or SSD Dead?
If your status says “Caution,” your drive is not dead yet, but it is actively dying.

Hardware degradation is a one-way street. A drive with bad sectors might continue to work for two years, or it might completely brick itself in two days. The problem is that the drive can no longer be trusted. If you keep using it for important work, it is a gamble.

 

(Note: If the status is red and says “Bad,” the drive has already failed catastrophically. Stop using it immediately).

Step-by-Step: What to Do When You See “Caution”
Do not ignore the yellow badge. Follow these steps immediately:

Step 1: Stop Heavy Usage
Do not download large games, render heavy video files, or run intense disk defragmentation software. The harder the drive works, the faster those bad sectors will spread.

Step 2: Back Up Your Essential Data (Right Now)
This is the most important step. Grab a USB flash drive, an external hard drive, or open a cloud storage service like Google Drive or Dropbox.

Copy your irreplaceable files first: Family photos, tax documents, school assignments, and work projects.

Do not bother backing up installed programs or games; you can always redownload those later. Focus only on personal files.

Step 3: Plan for a Replacement
Once your data is safe, you need to buy a replacement drive. Software cannot fix physical hardware damage. If you are using an older mechanical Hard Drive (HDD), this is the perfect excuse to upgrade to a much faster Solid State Drive (SSD) or NVMe M.2 drive.

Can You Fix a Drive in “Caution” Status?
A common myth online is that you can “fix” bad sectors by running the Windows chkdsk /r command in the command prompt.

This is false. Software cannot repair physical damage on a magnetic disk or a dead flash memory cell on an SSD. Running a disk check simply tells Windows to locate the broken sectors and build a digital fence around them so the PC stops trying to use them.

While this might temporarily stop your computer from crashing, it puts immense stress on an already dying drive. In many cases, running a heavy disk check on a “Caution” drive is the final nail in the coffin that kills it completely.

The only true fix is a hardware replacement.

• Frequently Asked Questions (FAQ)
• Can I still use a drive with a Caution status for gaming?
  If you have already backed up your important files and only use the drive to store easily downloadable Steam games, you can keep using it until it completely dies. Just expect longer load times and potential game crashes.
• Why did my drive get bad sectors?For mechanical HDDs, it is usually age, physical bumps/drops while the drive is spinning, or extreme heat. For SSDs, it is usually reaching the limit of its write lifespan (TBW – Terabytes Written) or a sudden power outage that corrupted the flash memory.
• Does formatting the drive remove the Caution status?
• No. Formatting wipes the data, but the S.M.A.R.T. log is permanently stored on the drive’s internal memory chip. The bad sectors will still be there, and CrystalDiskInfo will still read them.

How to Fix ‘Caution’ Status in CrystalDiskInfo

You launched CrystalDiskInfo to check your drive’s health, and instead of a reassuring blue ‘Good’ icon, you’re staring at a bright yellow ‘Caution’ health status. Your heart drops. Is my data safe? Is my SSD dying? Can this be fixed?

The ‘Caution’ status is the most critical warning most users will see. It is CrystalDiskInfo telling you that while your drive has not failed yet, it has exceeded safe thresholds on vital health parameters.

This comprehensive guide will walk you through exactly what ‘Caution’ means, how to identify the specific failure points, how to rescue your data, and what steps (if any) you can take to “fix” the status.

What Does the ‘Caution’ Status Actually Mean?

CrystalDiskInfo doesn’t guess your drive’s health; it reads the S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data embedded in your storage drive’s firmware.

When the drive’s internal logic detects that certain critical attributes—like how many spare sectors it has used up or how many errors it can’t correct—have crossed a pre-set failure threshold, it flags that attribute. CrystalDiskInfo then aggregates these flags and displays the ‘Caution’ status.

Think of it like a ‘Check Engine’ light: Your car is still driving, but you are at high risk of a breakdown.

The Most Common Causes of ‘Caution’ (The Big Three)

While S.M.A.R.T. monitors dozens of attributes, ‘Caution’ is almost always triggered by one of these three critical errors:

1. Reallocated Sectors Count (05): This is the most common trigger. When a drive finds a corrupted sector, it retires it and moves the data to a ‘spare’ sector. When this count rises, your drive is running out of spares.

2. Current Pending Sector Count (C5): These are “unstable” sectors that the drive is waiting to test. If the test fails, they become Reallocated Sectors. This count often indicates an imminent failure.

3. Uncorrectable Sector Count (C6): This is the most serious. It means the drive encountered an error it could not read or write, even after multiple attempts. Data corruption has likely already occurred.

Step 1: Immediate Action—The Triage (DO NOT SKIP)

If you see the yellow ‘Caution’ icon, you must assume your drive is on its deathbed. You have one priority.

🛑 STOP WHAT YOU ARE DOING AND BACKUP NOW.

Do not run malware scans. Do not defragment. Do not install new software. Every read/write operation could be the one that causes the drive to fail completely.

Your Action Plan:

1. Connect an external hard drive, USB flash drive, or use a cloud storage service.

2. Manually copy your most essential files immediately: documents, photos, saved games, and irreplaceable data.

3. If you have large amounts of data, back up the most critical items first. If the drive fails mid-backup, at least you saved the essentials.

Only after your critical data is safe should you proceed to troubleshooting.

Step 2: Identify the Specific Failure Point

To know if a “fix” is possible, we need to know exactly which S.M.A.R.T. attribute triggered the warning.

• Look at the Main Interface: (See the highlighted example below)

• Locate the Red or Yellow Markers: In the list of ID attributes, look for the rows marked with a yellow or red dot.

• Read the Attribute Name: Is it 05, C5, or C6?

This screenshot shows a drive that is failing due to a critical increase in Reallocated Sectors (05) and Current Pending Sectors (C5). The red RAW values are the specific counts of those failures.

Caption: Identifying the Failing S.M.A.R.T. Data. This close-up view zooms in on the source of the problem. The small indicators next to ID 05 (Reallocated Sectors Count), C5 (Current Pending Sector Count), and C6 (Uncorrectable Sector Count) are now glowing red. Arrows directly link these flashing critical S.M.A.R.T. data points to the bright yellow ‘Caution’ status box, pinpointing the specific physical failures triggering the alert.

Step 3: Can You Actually “Fix” the ‘Caution’ Status?

Here is the hard truth: You cannot physically repair a failing hard drive or SSD.

Physical sector damage cannot be undone. You cannot “repair” the Reallocated Sectors Count. Once a sector is retired, it is gone forever. Your drive’s capacity has permanently degraded.

However, you can sometimes “fix” the ‘Caution’ status listing in CrystalDiskInfo by forcing the drive to re-evaluate unstable sectors (C5) or, in rare cases, by adjusting the application’s warning thresholds.

Here are the potential remedies based on your specific S.M.A.R.T. error:

Scenario A: Your Error is C5: Current Pending Sector Count (Potentially Fixable Status)

This is the only scenario where the ‘Caution’ status might disappear. Pending Sectors are unstable sectors the drive hasn’t decided what to do with yet. They might be bad, or they might just be experiencing a temporary write error.

The “Fix”: You must force the drive to write data to those specific sectors.

1. Run a Full Disk Scan (Chkdsk): Open Command Prompt as Administrator and run chkdsk /r /f C: (replace C: with your drive letter). Windows will scan the entire drive and attempt to read and repair unstable sectors. This process can take hours and may stress a dying drive.

2. Use a Secure Erase/Zero-Fill Tool: If Chkdsk fails, the absolute best method is a “Zero-Fill” or “Secure Erase.” This uses specialized software (like the drive manufacturer’s Western Digital Dashboard, Samsung Magician, or bootable tools like DBAN) to write zeros to every single sector on the drive. This forces the drive’s firmware to test every pending sector.

If the Zero-Fill completes successfully and the pending sectors are either successfully written to or officially reallocated (moved to ID 05), the C5: Current Pending Sector Count will drop back to zero, and the ‘Caution’ status (assuming no other errors) will return to blue ‘Good.’ Your drive is still permanently weaker, but the imminent warning is gone.

Scenario B: Your Error is 05: Reallocated Sectors Count (Not Fixable)

This cannot be fixed. The drive has already used up some of its spare sectors. The only outcome is that this number will eventually increase.

• The Recommendation: Reallocated sectors indicate physical degradation. You must replace this drive as soon as possible. It is no longer reliable for operating system use or critical data storage. You might repurpose it for non-essential data (like a scratch disk for video editing or a temporary game installation drive), but only after a full Zero-Fill to stabilize it.

Scenario C: Your Error is C6: Uncorrectable Sector Count (Urgent Replacement Required)

This cannot be fixed. This is the most serious S.M.A.R.T. failure. It means your drive cannot read or write data from certain sectors, and it has no spares left to use.

• The Recommendation: This drive is a data loss event waiting to happen. Stop using it immediately. Do not attempt to repair it. Replace it now.

Step 4: The Last Resort—Hiding the Warning (Use with Caution)

Sometimes, a drive may have a very low, stable number of reallocated sectors (e.g., 1 or 2 reallocated sectors that haven’t changed in three years). If you have stabilized the drive (via a Zero-Fill) and confirmed the counts are not increasing, you can manually adjust CrystalDiskInfo’s health thresholds to stop the ‘Caution’ warning.

WARNING: This does not fix the drive. It only hides the warning. Use this only on non-critical drives.

1. Open CrystalDiskInfo.

2. Go to Function > Health Status Setting.

3. Locate the specific attribute causing the ‘Caution’ (e.g., Reallocated Sectors Count).

4. Move the slider slightly to the right, increasing the threshold at which the warning triggers.

If the threshold is set above the current count, the health status will return to a blue ‘Good.’ Monitor this drive closely. If the counts begin to rise again, your “fix” has failed.

Summary and Final Recommendation

The yellow ‘Caution’ status in CrystalDiskInfo is not a bug; it is a critical health advisory from your storage hardware.

CrystalDiskInfo Status	Meaning	Data Safety	Action
Good (Blue)	No critical S.M.A.R.T. errors.	Safe	Normal use. Monitor periodically.
Caution (Yellow)	Critical attributes (05, C5, C6) have exceeded thresholds. Drive is degrading.	At Risk	BACKUP NOW. Identify the specific error. Stabilize C5 if possible. Replace 05/C6 drives.
Bad (Red)	Drive has failed or is in an active state of failure.	Extreme Risk / Data Lost	Stop use immediately. Seek professional data recovery if data is not backed up.