File Checksum

Drop any file to generate its checksum. Paste an expected hash to verify the file is intact and hasn't been tampered with. Your file never leaves your browser.

Drop a file

Drop any file here

or click to browse — all processing is local

ALGORITHM

DISPLAY

Drop any file to generate its checksum. Compare against a publisher's hash to verify integrity.

Processed locally

How it works

File hashing uses the browser's built-in SubtleCrypto API (SHA-256). The file is read into memory locally and hashed on your device.

Your data stays local

Your file is read directly by the browser and never uploaded. No server receives it at any point.

Frequently asked questions

What is a file checksum?

A checksum is a hash of a file's contents. If even one byte changes, the hash changes completely. You can compare a checksum to a value published by a software author to verify you downloaded the correct file.

Which algorithm should I use for verification?

Use whatever algorithm the publisher provides. SHA-256 is the most common today. Avoid MD5 and SHA-1 for security-sensitive verification.

Is my file uploaded anywhere?

No. The file is read directly by your browser using the File API and hashed with the SubtleCrypto API. It never leaves your device.