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Enter text to see MD5, SHA-1, SHA-256 and SHA-512 hashes.

Computes MD5, SHA-1, SHA-256 and SHA-512 at once. Everything runs in your browser — your input is never sent to a server. MD5 and SHA-1 have known collisions, so prefer SHA-256 or stronger for security uses (passwords, signatures).

What a hash is and when to use one

A hash turns data of any length into a value of fixed length. The same input always gives the same result, and changing a single character produces a completely different value. You cannot recover the original from the result.

That makes it useful for checking a file was not corrupted in transit (a checksum), or comparing whether two pieces of data match without looking at either. Git commit IDs and the SHA-256 values printed on download pages are both hashes.

MD5 and SHA-1 have known collisions — different inputs that produce the same value — so they are no longer used for security. Prefer SHA-256 for integrity checks. For storing passwords a plain hash is not enough; use a purpose-built algorithm such as bcrypt.