SHA-1 hash generator
This tool calculates the 160-bit SHA-1 hash of text and shows it as 40 hexadecimal characters. Developers use it to match checksums from older systems and APIs that still use SHA-1.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
hello
aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d
How to use the sha-1 hash generator
- Type or paste your text into the Text to hash box.
- Choose Hexadecimal letters: Lowercase or Uppercase.
- Press Run.
- Use Copy result to copy the hash.
How it works
Your text is encoded as UTF-8 and hashed with the SHA-1 function built into your browser (Web Crypto).
SHA-1 is not collision resistant: researchers have produced two different files with the same SHA-1 hash. Do not use it for signatures, certificates or passwords; choose SHA-256 or SHA-512 instead.
Lowercase and uppercase hex letters describe the same hash, so pick the form the other system expects.
Text with an unpaired surrogate (half of an emoji) is rejected, and the limit is 1,000,000 characters.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
Is SHA-1 still safe?
Not for security. A practical SHA-1 collision was published in 2017, so SHA-1 should only be used for compatibility with older systems.
How long is a SHA-1 hash?
160 bits, shown as 40 hexadecimal characters.
What should I use instead of SHA-1?
Use SHA-256 for general hashing. For passwords, use a slow password hashing function such as bcrypt, scrypt or Argon2, not a plain hash.
Is my text uploaded?
No. It runs in your browser, and nothing you paste is sent to a server.