BLAKE2b hash
Compute a BLAKE2b digest of any file, on your device.
Runs on your device. The file is never uploaded.
BLAKE2b hash returns hash-wasm's default 512 bit digest, 128 lowercase hex characters, from the 64-bit word variant suited to 64-bit machines. Drop several files and each is hashed on its own. Only your bytes are passed, so the keyed and personalised modes BLAKE2b defines stay out of reach; HMAC is the tool for a keyed digest.
Questions
How long is the digest?
512 bits, or 128 lowercase hex characters. BLAKE2b can be asked for shorter outputs, but this tool takes the hash-wasm default size and exposes no length option, so you always get the full 64 bytes. A digest produced elsewhere at a shorter length will not match what you see here.
What is the difference between BLAKE2b and BLAKE2s?
The word size they are tuned for. BLAKE2b uses 64-bit words and suits 64-bit machines, with a 512-bit default digest. BLAKE2s uses 32-bit words for smaller and embedded platforms, with a 256-bit default. They are different algorithms, so their digests never match, even at the same output length.
Is BLAKE2b a secure hash?
It is a cryptographic hash, designed as a successor to BLAKE from the SHA-3 competition, and it is in a completely different category from the checksums on this site such as CRC32 or xxHash. Use it where a format or a counterpart asks for BLAKE2b; use SHA-256 where you need the most widely supported option.
Can I use a key, like a MAC?
Not here. BLAKE2b supports keyed hashing, but this tool passes only your file bytes, with no key and no personalisation. For a keyed digest use the HMAC tool, which takes a key and lets you pick MD5, SHA1, SHA256, SHA384 or SHA512.
Can I hash a batch of files?
Yes. Drop as many as you like and each returns its own two line result, the title with your file name followed by the digest. Nothing is uploaded at any point. For one file across every algorithm at once, Generate all hashes prints the whole hash-wasm table, BLAKE2b included.