Hash Generator

A hash function takes any input and produces a fixed-length string that's practically unique to that input — change even one character and the entire hash comes out completely different. This computes SHA-1, SHA-256, SHA-384 and SHA-512 of any text at once, using the browser's own Web Crypto API rather than sending anything to a server.

SHA-256, SHA-384, SHA-512 — pick by length, not much else

These are all part of the same SHA-2 family and are all currently considered secure. The difference between them is output length — SHA-256 produces 64 hex characters, SHA-512 produces 128 — and, correspondingly, the resistance margin against future attacks. SHA-256 is the practical default used almost everywhere: file integrity checks, checksums, Git commit hashing (in newer configurations), and password-hashing schemes built on top of it.

What hashing is actually for

Hashing is one-way — there's no operation that recovers the original text from the hash, which is exactly the point. It's used to verify a file or message hasn't been altered (compare the hash of what you received against the hash the sender published), and as a building block inside password storage systems, where a service stores the hash of a password rather than the password itself.

Why SHA-1 is included but not recommended

SHA-1 is offered only for checking against older systems that still use it — it has known collision attacks (two different inputs producing the same hash), which breaks its security guarantees for anything that matters. Use SHA-256 or higher for anything new; SHA-1 output here is for compatibility, not for new security-sensitive work.