Algorithm reference

SHA-1 hash calculator

SHA-1 is widely interoperable but must not be used where collision resistance matters.

Collision-broken 160-bit output 40 hex characters

Digest calculator

Text to hash

Private result

Never enter a real account password or any other secret. Submitted text is processed by the server, but never placed in the URL, logs, analytics, or ads.

Practical guidance

About SHA-1

Legacy checksums and compatibility only. Prefer SHA-256 for new work.

Collision resistance

Practical chosen-prefix collision attacks are public.

Examples

Use SHA-1

Command line

printf %s "hello" | sha1sum

Go

sum := sha1.Sum([]byte("hello")); fmt.Printf("%x\n", sum)

Python

hashlib.sha1(b"hello").hexdigest()

JavaScript / browser

crypto.subtle.digest("SHA-1", new TextEncoder().encode("hello"))

Common password examplesPublic deterministic compatibility pages