Keccak-512 Hash Generator
Generate the Keccak-512 hash of any text instantly in your browser. UTF-8, hex or Base64 input; hex or Base64 output. Free, private, no upload.
Runs entirely in your browser. Your data is never uploaded.
What is Keccak-512 Hash Generator?
Keccak-512 is the original Keccak hash (the SHA-3 competition winner as submitted, 2011) with a 512-bit output, before NIST changed the padding for FIPS 202. This tool computes the 512-bit Keccak-512 digest of text or raw bytes (hex or Base64) as you type and shows it as 128 hex characters or Base64.
How to use Keccak-512 Hash Generator
- Type or paste your input into Text to hash — the digest updates as you type (an empty box shows the hash of empty input).
- Choose the Input encoding: Text (UTF-8) hashes the characters as UTF-8, Hex bytes or Base64 hash the decoded raw bytes.
- Pick the Output format (hex lowercase, hex uppercase or Base64) and click Copy.
Example
abc
18587dc2ea106b9a1563e32b3312421ca164c7f1f07bc922a9c83d77cea3a1e5d0c69910739025372dc14ac9642629379540c17e2a65b19d77aa511a9d00bb96
Keccak-512 of the 3 ASCII bytes "abc" (UTF-8, hex lowercase output), the standard test vector.
When to use Keccak-512 Hash Generator
Use the Keccak-512 text tool to hash strings: reproduce a value from documentation or code, build test vectors, compare an API signature input, or check what a program should output. Do not use it to check a downloaded file: copying file contents into a text box changes line endings and encoding, so use the Keccak-512 file checksum tool. For new standards-based work (FIPS, NIST), use SHA3-512 instead.
How Keccak-512 Hash Generator works
Keccak-512 absorbs the input into the 1600-bit Keccak-f[1600] state in 576-bit blocks (capacity 1024 bits) and applies 24 permutation rounds per block. It pads with the original Keccak rule pad10*1 (byte 0x01 … 0x80), without the 01 domain suffix that FIPS 202 added. The first 512 bits of the state are the digest, which is why Keccak-512 and SHA3-512 differ for every input. The text is first converted to bytes (UTF-8 by default), so the same characters always give the same hash.
Common Use Cases
- Check the expected Keccak-512 of a string in a unit test or fixture
- Hash hex bytes copied from a debugger, packet capture or protocol spec
- Compare Keccak-512 output between two programming languages that disagree
- Generate deterministic identifiers or cache keys from text
- Get the Base64 form of a Keccak-512 digest for headers or configuration files
Security Note
Keccak-512 has no known practical attacks. Plain hashes are also not suitable for storing passwords: use a slow, salted password hash such as Argon2, scrypt or bcrypt. Everything is computed locally in your browser; nothing you type is sent anywhere.
FAQs
What is the difference between Keccak-512 and SHA3-512?
Only the padding: Keccak uses 0x01, SHA-3 uses 0x06 (a two-bit domain suffix). Same permutation and rate, completely different outputs. For an empty input Keccak-512 and SHA3-512 give unrelated digests.
Who uses Keccak-512?
Mostly software written before FIPS 202 was finalized and some blockchain projects. Ethereum uses Keccak-256; the 224, 384 and 512-bit variants appear in older libraries and test suites.
Why does the hash change completely when I change one character?
That is the avalanche effect every cryptographic hash is designed for: flipping one input bit changes about half of the 512 output bits, so similar inputs give unrelated digests.
Does a trailing space or newline matter?
Yes. The hash covers every byte, so abc and abc followed by a newline give different Keccak-512 values. Make sure the input contains exactly the bytes you intend to hash.