SHA-3 Hash Generator

What this tool does

It computes the SHA-3 hash of any text you type, in four sizes at once: SHA3-224, SHA3-256, SHA3-384 and SHA3-512. SHA-3 is the standard published by NIST as FIPS 202. The calculation runs in your browser using the open-source noble-hashes library, so your text is not sent anywhere. We also checked the tool's output for all four sizes against the SHA-3 implementation built into Node.js (OpenSSL), and the results are identical.

How to use it

1. Type or paste your text.
2. Click Generate.
3. Copy the digest you need. Each line is labelled with its size.

Check it against known values

A good habit with any hash tool is to test it on a known input. For the text abc (no spaces, no new line), the correct digests are:

The SHA3-256 hash of an empty input is a7ffc6f8bf1ed76651c14756a061d662f580ff4de43b49fa82d80a4b80f8434a. If your own results differ from these, check the input first, because tiny differences in the text change the whole hash.

Why the input must match exactly

• Case counts. The SHA3-256 hash of Abc is completely different from that of abc.
• A trailing new line counts. abc followed by a line break hashes to 855e77bb9d8fc068ca812a39d07bad50dc012d7f07c346d7e56a4f25075e4070, not the value above. This is the most common reason a hash does not match one produced by a command-line tool.
• Text is hashed as UTF-8. Accented letters and symbols are converted to their UTF-8 bytes first, which is what most tools and programming languages do. If another system uses a different encoding, hashes of non-English text will not match.

SHA-3 versus SHA-256 and Keccak

• Not the same as SHA-256. SHA-256 belongs to the older SHA-2 family. For abc it gives ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad, which has nothing in common with the SHA3-256 value even though both are 64 hex characters long. SHA-3 uses a different design (Keccak) and was chosen as an alternative, not because SHA-2 was broken.
• Not the same as the "Keccak-256" used by Ethereum. That function is the original Keccak submission, which differs from final NIST SHA-3 in how input is padded. For the empty input it gives c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470, whereas SHA3-256 gives the a7ffc6f8... value above. This tool computes NIST SHA-3 only.

What this tool is not for

• Storing passwords. SHA-3, like SHA-256, is a fast hash, which is the wrong choice for password storage. Use a slow password-hashing function such as bcrypt, scrypt or Argon2.
• Hashing files. The tool hashes text you paste, not files.
• Keyed hashes (HMAC) and other variants such as SHAKE are not offered.

For other developer encodings, see the Base64 encoder and the UUID generator, and use the password generator to create strong passwords before you store them with a proper password-hashing function.