How to Run Check Disk on Windows 10 (CHKDSK Guide)

Windows 10 includes a built-in tool called Check Disk — or CHKDSK — that scans your hard drive or SSD for file system errors, bad sectors, and corruption. It's one of the most reliable first steps when you're dealing with slow performance, unexpected crashes, or files that won't open. Running it correctly depends on how your drive is set up, what kind of problem you're dealing with, and how comfortable you are with the command line.

What Check Disk Actually Does

CHKDSK (short for Check Disk) is a Windows system utility that examines the integrity of a storage volume. It checks two main things:

• File system metadata — the index Windows uses to track where files are stored on the drive
• Physical sectors — actual storage blocks on the drive that may have become damaged or unreadable

When errors are found, CHKDSK can either report them (read-only mode) or attempt to fix them automatically. For mechanical HDDs, it can also scan for and quarantine bad sectors so Windows stops trying to write data to damaged areas. On SSDs, bad sector scanning is less relevant because of how solid-state storage works, but file system errors can still occur and CHKDSK handles those just as well.

Two Ways to Run CHKDSK on Windows 10

Method 1: File Explorer (No Command Line Required)

This is the most accessible option for most users.

1. Open File Explorer and go to This PC
2. Right-click the drive you want to check (usually C:) and select Properties
3. Click the Tools tab
4. Under Error checking, click Check
5. Windows may say no errors were found — if you want a full scan anyway, click Scan drive

This method runs a basic scan and is fine for routine maintenance checks. It won't give you detailed output, but it surfaces most common file system issues without requiring any technical knowledge.

Method 2: Command Prompt (More Control) 💻

The command line version gives you access to specific flags that control how deep the scan goes and what gets fixed.

To open an elevated Command Prompt:

1. Press Windows + S, type cmd
2. Right-click Command Prompt and select Run as administrator

Basic CHKDSK commands:

Replace C: with whichever drive letter you're checking.

What Happens When CHKDSK Needs to Scan the System Drive

If you run chkdsk C: /f on your active Windows drive (the one Windows is running from), the tool can't lock that volume while the OS is using it. Windows will prompt you to schedule the scan for the next restart. Type Y and press Enter, then restart your PC. The scan runs automatically before Windows loads, which can take anywhere from a few minutes to over an hour depending on drive size and condition.

Understanding the Output

Once the scan completes, CHKDSK displays a summary. Key things to look for:

• "Windows has scanned the file system and found no problems" — drive is healthy
• "Corrupt file records" or "bad clusters" — errors were found, and with /f or /r, CHKDSK attempted repairs
• "Windows replaced bad clusters" — sectors were remapped (relevant mainly on HDDs)

You can also view CHKDSK results after a reboot scan by opening Event Viewer → Windows Logs → Application → look for source Wininit.

Factors That Affect What You Should Do

Not everyone should run the same CHKDSK command, and the right approach depends on several variables:

Drive type matters. Running /r on a large HDD can take hours. On an SSD, a full bad sector scan is less necessary and some technicians skip /r entirely on solid-state drives, using /f alone instead.

Drive size and fill level. A nearly full 4TB drive takes significantly longer to scan than a 256GB drive with free space.

How severe the problem is. If your PC is crashing repeatedly, you may need to run CHKDSK from Windows Recovery Environment rather than from within Windows — because the OS itself may not be stable enough to schedule and complete a standard scan.

Age of the drive. 🔍 An older HDD with multiple bad sectors flagged by CHKDSK is a different situation than a newer drive showing a single file system error. CHKDSK can repair the latter; it's not a fix for hardware that's genuinely failing.

Skill level. The File Explorer method is safe for anyone. The /r command with its longer runtime and more aggressive scanning is better suited to users who understand they're committing to a potentially hours-long process.

When CHKDSK Isn't Enough

CHKDSK fixes logical errors and marks bad sectors. It doesn't:

• Recover deleted files
• Replace a failing drive
• Fix problems caused by malware (though it may surface corruption malware caused)
• Repair corrupted Windows system files (that's a job for sfc /scannow or DISM)

If CHKDSK keeps finding errors every time you run it — especially on an HDD — that's a signal the drive's physical condition is deteriorating, not just a software issue that can be patched.

What CHKDSK tells you about your specific drive, under your specific workload, on your specific version of Windows 10 — that's the information that determines what the right next step actually is.