File checksum generator
Calculate SHA-256, SHA-384 or SHA-512 checksums for local files without uploading them.
A checksum is a compact fingerprint of a file. If one byte changes, the digest changes, making hashes useful for checking that a download arrived intact or that two copies are identical.
The file stays on your device. Your browser reads it into memory and calculates the selected SHA-2 digest with its built-in cryptography implementation; there is no upload endpoint.
Choose the algorithm named by the publisher
SHA-256 is the most common choice. A checksum only verifies a file when you compare it with a trusted value published separately.
Comparison is exact
Hexadecimal hashes are not case-sensitive, but every character must otherwise match. A mismatch means the files differ.
Frequently asked questions
Does this prove a file is safe?
No. It proves only that a file matches another copy with the same digest. Trust depends on where the expected checksum came from.
Is my file uploaded?
No. The File and Web Crypto APIs process it locally in your browser.
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