A fingerprint for any text
A cryptographic hash reduces any input to a fixed-length string that changes completely if even one character of the input changes. That makes it a fingerprint: two pieces of text match if and only if their hashes match. This tool computes four SHA variants at once so you can grab whichever a given system expects.
Computed with real primitives, locally
The digests come from the browser's Web Crypto API — the same audited implementation used for secure connections — not a reimplementation. And because it runs on your device, the text you hash is never transmitted, so this is safe for values you would not paste into an online service.