SHA-1 Hash
Compute the SHA-1 digest of text, for example to match an identifier produced by an older system.
Your input stays in your browser. Nothing is uploaded.
About this tool
SHA-1 produces a 160-bit digest, written as 40 lowercase hex characters, and is computed here with the browser's Web Crypto API after UTF-8 encoding. Practical SHA-1 collisions have been demonstrated since 2017, so it should not be used for digital signatures or certificates. It still appears in legacy formats and some version-control and caching systems. Fast hashes like this one are not suitable for storing passwords. Use a slow password-hashing function such as Argon2, scrypt, or bcrypt for that.
How to use it
- Paste or type the text.
- Copy the 40-character SHA-1 digest.
Examples
"hello"
aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d
Empty string
da39a3ee5e6b4b0d3255bfef95601890afd80709
FAQ
Is SHA-1 still safe?
Not for anything where an attacker could choose the input. For new work, use SHA-256 or SHA-512.
Why is the digest 40 characters?
160 bits is 20 bytes, and each byte is written as two hex characters.
Is my text uploaded?
No. Hashing runs in your browser.