Hash Generator
Generate SHA-256, SHA-1, SHA-384 and SHA-512 hashes of text, right in your browser.
About this tool
Hashes are worked out with the Web Crypto API built into your browser, on the exact text you enter encoded as UTF-8. Nothing is sent anywhere. MD5 is not offered because browsers do not include it and it is no longer considered secure.
A cryptographic hash turns any text into a fixed-length fingerprint: the same input always gives the same hash, but changing a single character changes it completely. Developers use hashes to check that files and messages have not been altered, to compare values without storing them, and to test code. Type or paste text to get its SHA-256, SHA-1, SHA-384 and SHA-512 hashes instantly; everything is calculated in your browser.
How to use the Hash Generator
- Type or paste the text you want to hash.
- Choose lowercase or uppercase hexadecimal.
- Copy the hash you need; SHA-256 is the most widely used.
Hashing hello world
The SHA-256 hash of hello world (lowercase, no full stop or new line) is b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9. Adding a capital H, Hello world, gives 64ec88ca00b268e5ba1a35678a1b5316d212f4f366b2477232534a8aeca37f3c, which is completely different. That sensitivity is what makes hashes useful for spotting changes.
Which hash should I use?
SHA-256 is part of the SHA-2 family and is the standard choice today for checksums, digital signatures and blockchain systems; it produces 64 hexadecimal characters. SHA-384 and SHA-512 are longer members of the same family. SHA-1 (40 characters) is still seen in older systems and Git, but practical collisions have been demonstrated, so it should not be used for security. Hashing is one-way: you cannot turn a hash back into the text, although short or common inputs can be found by guessing. That is why passwords should never be stored as a plain SHA hash; use a slow password-hashing function such as bcrypt or Argon2 with a salt instead. Hashes also depend on the exact bytes, so a trailing space, a new line or a different text encoding changes the result.
Frequently asked questions
Can a SHA-256 hash be reversed?
No. Hash functions are designed to be one-way. Simple inputs can sometimes be guessed by trying many possibilities, but the hash itself cannot be decoded.
Why does my hash not match another tool?
Check for a trailing space or new line, different capitalisation, or a different text encoding. This tool hashes the text exactly as entered, encoded as UTF-8.
Is my text sent to a server?
No. The hash is calculated by your browser’s built-in Web Crypto API and never leaves your device.
Why is there no MD5?
MD5 is broken for security purposes and browsers do not provide it in Web Crypto. Use SHA-256 for new work.