Private by design: runs entirely in your browser
Hash generator
MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE3 and more, side by side as you type. Hash files of any size, check downloads against their checksums, and make HMACs. Nothing leaves your device.
Input
Hashes (of empty input)
- MD5128-bitbroken
d41d8cd98f00b204e9800998ecf8427e - SHA-1160-bitbroken
da39a3ee5e6b4b0d3255bfef95601890afd80709 - SHA-256256-bitsecure
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 - SHA-384384-bitsecure
38b060a751ac96384cd9327eb1b1e36a21fdb71114be07434c0cc7bf63f6e1da274edebfe76f65fbd51ad2f14898b95b - SHA-512512-bitsecure
cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e - SHA3-256256-bitsecure
a7ffc6f8bf1ed76651c14756a061d662f580ff4de43b49fa82d80a4b80f8434a - SHA3-512512-bitsecure
a69f73cca23a9ac5c8b567dc185a756e97c982164fe25859e0d1dcc1475c80a615b2123af1f5f94c11e3e9402c3ac558f500199d95b6d3e301758586281dcd26 - BLAKE2b-512512-bitsecure
786a02f742015903c6c6fd852552d272912f4740e15847618a86e217f71f5419d25e1031afee585313896444934eb04b903a685b1448b755d56f701afe9be2ce - BLAKE3256-bitsecure
af1349b9f5f9a1a6a0404dea36dcc9499bcb25c9adc112b7cc9a93cae41f3262 - CRC-3232-bitchecksum
00000000
Tools
What is a hash?
A cryptographic hash function turns any amount of data, from one byte to a whole disk image, into a short fingerprint of a fixed size. A good one is:
- Deterministic: the same input always gives the same hash, on any computer.
- One-way: you can't work back from the hash to the input.
- Collision-resistant: nobody can find two different inputs with the same hash.
Change one character and the whole hash changes. This is the avalanche effect. Here is SHA-256 of two strings that differ only in their last character:
"Hello, World!"
dffd6021bb2bd5b0af676290809ec3a53191dd81c7f70a4b28688a362182986f
"Hello, World."
02b5dcd5f0ef1a39cffec5f8b625ec20bffcf918e4efd3f54babec4eae03b347
63 of the 64 hex digits differ (highlighted). For unrelated random hashes you'd expect about 60.
Algorithms
| Algorithm | Output | Status | Notes |
|---|---|---|---|
| MD5 | 128 bits · 32 hex digits | broken | Broken: collisions take seconds. Fine for spotting accidental changes. |
| SHA-1 | 160 bits · 40 hex digits | broken | Broken: collisions have been made (SHAttered, 2017). Still used by Git. |
| SHA-224 | 224 bits · 56 hex digits | secure | SHA-256 with a different start and a shorter output. |
| SHA-256 | 256 bits · 64 hex digits | secure | The most widely used hash: TLS, code signing, Bitcoin, checksums. |
| SHA-384 | 384 bits · 96 hex digits | secure | SHA-512 with a different start, cut to 384 bits. |
| SHA-512 | 512 bits · 128 hex digits | secure | Uses 64-bit words, so it's often faster than SHA-256 on 64-bit CPUs. |
| SHA-512/224 | 224 bits · 56 hex digits | secure | SHA-512 with its own start, cut to 224 bits. |
| SHA-512/256 | 256 bits · 64 hex digits | secure | SHA-512 with its own start, cut to 256 bits. |
| SHA3-224 | 224 bits · 56 hex digits | secure | Keccak sponge, standardised in FIPS 202. |
| SHA3-256 | 256 bits · 64 hex digits | secure | A different design from SHA-2, so a backup if SHA-2 is ever broken. |
| SHA3-384 | 384 bits · 96 hex digits | secure | Keccak sponge, standardised in FIPS 202. |
| SHA3-512 | 512 bits · 128 hex digits | secure | Keccak sponge, standardised in FIPS 202. |
| Keccak-256 | 256 bits · 64 hex digits | secure | The original Keccak padding, as used by Ethereum. Differs from SHA3-256. |
| SHAKE128 | 256 bits · 64 hex digits | secure | Extendable output; shown here with 256 bits of output. |
| SHAKE256 | 512 bits · 128 hex digits | secure | Extendable output; shown here with 512 bits of output. |
| BLAKE2b-512 | 512 bits · 128 hex digits | secure | Fast and secure; used by Argon2, WireGuard and libsodium. |
| BLAKE2s-256 | 256 bits · 64 hex digits | secure | BLAKE2 tuned for 32-bit and small CPUs. |
| BLAKE3 | 256 bits · 64 hex digits | secure | The newest BLAKE: a tree hash built for speed and parallelism. |
| RIPEMD-160 | 160 bits · 40 hex digits | secure | Used with SHA-256 for Bitcoin addresses. |
| CRC-32 | 32 bits · 8 hex digits | checksum | A checksum, not a cryptographic hash: catches accidental errors only. |
Frequently asked questions
Is my data sent to a server?+
No. Every hash is worked out by JavaScript in your browser. Text, files and HMAC keys never leave your device, so it's safe to hash confidential files, and it keeps working offline once the page has loaded.
Can a hash be reversed or decrypted?+
No. A hash is a one-way fingerprint: there's no key to undo it, and endless inputs share each hash. Sites that claim to "decrypt" MD5 or SHA-1 look the hash up in a big table of strings they've already hashed. That's why short or common passwords hashed with plain MD5 or SHA-256 are easy to recover.
Is MD5 or SHA-1 safe to use?+
Not for security. Anyone can make two different files with the same MD5 hash in seconds, and SHA-1 collisions have been made too. They're still fine for spotting accidental corruption or as a cache key. For anything security-related use SHA-256, SHA-512, SHA-3 or BLAKE2/BLAKE3.
Should I hash passwords with SHA-256?+
No. General-purpose hashes are designed to be fast, so an attacker can try billions of guesses a second. Store passwords with a slow, salted password hash: Argon2id, scrypt, bcrypt or PBKDF2.
Why does my hash differ from another tool's?+
Usually the bytes differ, not the algorithm. Look for a trailing newline (echo adds one; use echo -n or printf), Windows CRLF line endings instead of LF, a text encoding other than UTF-8, or extra spaces. Also check both sides show the same format: hex or Base64.
What's the difference between SHA-3 and Keccak-256?+
Ethereum adopted Keccak before it was standardised. NIST then changed the padding when it published SHA-3 (FIPS 202), so SHA3-256 and Keccak-256 give different hashes for the same input. Ethereum and Solidity's keccak256 use the original Keccak.