Algorithms
HASH256
SHA-256 twice. Bitcoin transaction ids and block hashes and the Base58Check checksum
Hash / Cryptographic
HASH256 (double SHA-256)
SHA-256 twice, every txid and block hash.
- Digest
- 256-bit · 32 bytes
- HMAC
- no key mode
- Security
- 128-bit collision resistance
- Used by
- Bitcoin
1 option, 0 required
Sample
- hex
- bc62d4b80d9e36da29c16c5d4d9f11731f36052c72401a76c23c0fb5a9b74423
- base64
- vGLUuA2eNtopwWxdTZ8Rcx82BSxyQBp2wjwPtam3RCM=
Options
Access
- Create
create("hash256") - CLI
hashes hash256 'hello world' - Tryplayground with the sample above
- Kinsha256, sha384, sha512, sha512-half +11
SHA-256 of SHA-256. Bitcoin's txids, block hashes, merkle nodes, and the 4-byte checksum at the end of every Base58Check string.
create("hash256").hash("hello").digest;
// "9595c9df90075148eb06860365df33584b75bff782a510c6cd4883a419833d50"
create("sha256").hash(create("sha256").hash("hello", { encoding: "binary" }).digest).digest;
// the same, spelled out
The digest comes out in hash order. Block explorers print txids and block hashes byte-reversed, so compare against a reversed string or reverse the bytes first. Everybody trips over this once. No HMAC mode.