File Checksum Calculator
Choose a file to get its SHA-256, SHA-1, MD5 and SHA-512 checksums, then paste the value published on the download page to confirm it's a match.
Add this calculator to your website
Copy the code and paste it into your page's HTML. It's free; please keep the credit link.
Checking a checksum without a website
- Windows (PowerShell): Get-FileHash .\file.iso (SHA-256 by default) or Get-FileHash .\file.iso -Algorithm MD5
- Windows (Command Prompt): certutil -hashfile file.iso SHA256
- macOS: shasum -a 256 file.iso, or md5 file.iso
- Linux: sha256sum file.iso, or sha256sum -c SHA256SUMS to check a whole list
Checksum vs signature
A checksum on the same page as the download only protects against corruption: anyone who can replace the file can replace the checksum too. Projects that sign their releases (GPG, Sigstore, Authenticode) let you also verify who published the file, which is the stronger check for security-critical software.
Frequently asked questions
Why verify a checksum?
It proves the file you have is byte-for-byte the one the publisher released: not cut short by a broken download, and not swapped by a compromised mirror. This matters most for operating system images, installers and firmware.
The checksum doesn't match. What now?
Make sure you're comparing the same algorithm (SHA-256 vs SHA-1 vs MD5) and the same file version. If it still differs, delete the file and download it again from the official site; don't run it.
Is my file uploaded?
No. The file is read and hashed on your device, which is why even multi-gigabyte ISOs work without waiting for an upload.
Is what I paste sent to a server?
No. This tool runs entirely in your browser with JavaScript and the built-in Web Crypto API. Nothing you type, paste or open is uploaded or stored.