BYTETOOLS

File Checksum Calculator

Calculate SHA-1, SHA-256 and SHA-512 checksums of any file in your browser. Copy each hash and compare against an expected value to verify a download is intact.

Drop a file here or click to browseAny file type — hashed locally, never uploaded
  • SHA-1, SHA-256 and SHA-512 in one pass
  • Works on files of any type
  • Copy button for every checksum
  • Compare-against-expected with instant verdict
  • Case and whitespace insensitive comparison
  • 100% private — files are never uploaded

How to use the File Checksum Calculator

  1. 1

    Drop a file onto the tool or click to browse for one.

  2. 2

    Wait a moment while the SHA-1, SHA-256 and SHA-512 hashes are computed.

  3. 3

    Copy any checksum with its copy button.

  4. 4

    Paste the publisher's expected checksum into the compare box.

  5. 5

    Read the match or mismatch verdict to verify the file.

About the File Checksum Calculator

The ByteTools File Checksum Calculator computes cryptographic hashes of any file so you can verify it downloaded correctly and was not tampered with. Drop a file and it produces SHA-1, SHA-256 and SHA-512 digests using the browser's Web Crypto API on the file's raw bytes.

Paste the checksum a publisher lists next to a download into the compare box and the tool instantly tells you whether it matches, ignoring case and whitespace. This is the standard way to confirm that installers, ISO images and archives arrived intact.

The file is read and hashed entirely in your browser with JavaScript — it is never uploaded to any server. Large files are processed locally, so even multi-gigabyte downloads stay on your machine and remain completely private.

Frequently asked questions

What is a file checksum for?

A checksum is a fingerprint of a file's contents. Publishers list one next to a download so you can recompute it after downloading and confirm the file is complete and unaltered. If a single byte changes, the checksum changes completely.

Which checksum should I use?

Use the algorithm the publisher provides. SHA-256 is the modern standard for verifying downloads. SHA-512 offers a longer digest, while SHA-1 still appears on older projects but is considered weak for security-critical verification.

Does the file get uploaded to check it?

No. The file is read and hashed in your browser using the Web Crypto API. It never leaves your device, which is why even very large files can be checked here privately and why the tool works offline.

What does a mismatch mean?

A mismatch means the file you have does not match the expected checksum, so it may be corrupted, incomplete or altered. Download it again from the official source and re-check before trusting or running it.

Can I check very large files?

Yes. Because hashing happens locally, the practical limit is your device's memory rather than an upload size cap. Large ISO images and archives can take a few seconds to hash but are handled entirely on your machine.

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