SHA-256
The fingerprint behind half the internet.
Where it came from
SHA-256 is part of SHA-2, published by NIST in 2001 after SHA-1 started showing weaknesses. It produces a 256-bit (32-byte) digest. When SHA-1 was finally broken in 2017, SHA-256 was already everywhere.
It underpins TLS certificates, Git commit hashes (via SHA-1's successor plans), Bitcoin proof-of-work, and integrity checks for every download you verify.
How it works
SHA-256 is a one-way function: any input — a password, a file — maps to a fixed 32-byte fingerprint. Change one bit and the hash completely changes (the avalanche effect).
You cannot reverse it, but you can verify: hash your file and compare. UWC computes SHA-256 in your browser using the Web Crypto API — no upload, no server.
Hash with SHA-256
Fingerprint any text locally with SHA-256 — Web Crypto, nothing leaves the page.