IMD

Oracle

d136fd76signed

Which hash function does Bitcoin's proof of work use? Answer with the name in the form 'SHA-256'.

Answer

SHA-256
encoding
UTF-8 bytes of the exact string 'SHA-256', right-padded with zero bytes to 32 bytes
sources
, bitcoin core / bitcoin wiki: bitcoin's proof-of-work mining uses double sha-256 (sha256d) as its hashing algorithm, per the original bitcoin whitepaper (nakamoto, 2008) and bitcoin core's implementation (src/pow.cpp, src/hash.h)., bitcoin core / bitcoin wiki: bitcoin's proof-of-work uses the sha-256 hash function (double sha-256, applied twice) as specified in the original bitcoin whitepaper and implemented in bitcoind's mining/verification code., bitcoin core consensus code (src/pow.cpp / src/hash.h) and the bitcoin whitepaper (section 4, 'proof-of-work'), both of which specify double sha-256 as the hashing function used for bitcoin's proof-of-work., bitcoin core developer documentation (bitcoin.org/en/developer-guide) and the original bitcoin whitepaper, both stating that bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256, per block header)., bitcoin core developer documentation (bitcoin.org/en/developer-guide, 'proof of work' section) and the original bitcoin whitepaper (bitcoin.org/bitcoin.pdf), both of which specify that bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256)., bitcoin core developer documentation (developer.bitcoin.org) and the original bitcoin whitepaper by satoshi nakamoto (bitcoin.org/bitcoin.pdf, section 4, 'proof-of-work'), both of which specify that bitcoin's proof-of-work uses double sha-256 hashing, bitcoin core developer documentation (developer.bitcoin.org/reference/block_chain.html) and bitcoin.org's bitcoin whitepaper (satoshi nakamoto, 'bitcoin: a peer-to-peer electronic cash system', section 4, 'proof-of-work'), both of which state that bitcoin's proof-of-work mining uses the sha-256 hash function (applied twice, i.e. double-sha-256)., bitcoin core developer documentation / bitcoin whitepaper (nakamoto, 2008), section 4 'proof-of-work': bitcoin's proof-of-work scans for a value that, when hashed with sha-256, the hash begins with a number of zero bits., bitcoin core developer documentation / bitcoin whitepaper (satoshi nakamoto, 'bitcoin: a peer-to-peer electronic cash system', 2008), which specifies proof-of-work as scanning for a value whose double sha-256 hash is below a target, bitcoin core developer documentation / bitcoin wiki 'proof of work': bitcoin's proof-of-work function computes sha256(sha256(block_header)) and requires the resulting double-sha-256 hash to be below the target; the underlying hash function is sha-256, as specified in the original bitcoin whitepaper (nakamoto, 2008) and implemented in bitcoin core's block-header hashing (src/hash.h, chash256)., bitcoin core developer documentation / bitcoin wiki: 'proof of work' article states bitcoin uses sha-256 (double sha-256, sha256d) as its proof-of-work hash function (https://en.bitcoin.it/wiki/proof_of_work; bitcoin whitepaper by satoshi nakamoto, 2008)., bitcoin core developer documentation / bitcoin.org: bitcoin's proof-of-work mining algorithm hashes block headers with sha-256 applied twice (double-sha-256); the underlying hash function is sha-256., bitcoin core developer documentation and the original bitcoin whitepaper (nakamoto, 2008, section 4: 'proof-of-work'), which specify that block headers are hashed with sha-256 (applied twice) to find a value below the difficulty target., bitcoin core source (src/pow.cpp / src/hash.h) and the original bitcoin whitepaper (bitcoin.org/bitcoin.pdf), both of which specify bitcoin's proof-of-work hashing algorithm as sha-256 (applied twice, i.e. double sha-256, per block header), bitcoin core source (src/pow.cpp, getpowhash uses double sha-256) and the original bitcoin whitepaper (satoshi nakamoto, 'bitcoin: a peer-to-peer electronic cash system', 2008), which specifies sha-256 as the hash function used for the proof-of-work (hashcash-style) system., bitcoin core source and the bitcoin whitepaper (satoshi nakamoto, 2008) both specify that proof-of-work uses sha-256 (applied twice, i.e. double-sha-256) as the hash function for block hashing., bitcoin developer guide (bitcoin.org): 'bitcoin's block validation ... uses sha256(sha256()) as its proof-of-work hashing algorithm.' corroborated by the bitcoin whitepaper (satoshi nakamoto, 2008), section 4, which specifies proof-of-work via 'scanning for a value that when hashed, such as with sha-256...'., bitcoin developer guide (bitcoin.org): 'to prevent this problem, bitcoin uses a proof-of-work system... the hash of a block header must be lower than or equal to the current target for the block to be accepted, using double sha-256.', bitcoin developer guide (developer.bitcoin.org) and the bitcoin whitepaper (bitcoin.org/bitcoin.pdf), both of which specify sha-256 (applied twice, as double-sha-256) as the hash function used in bitcoin's proof-of-work mining algorithm, bitcoin developer guide (developer.bitcoin.org), 'proof of work': bitcoin's proof-of-work algorithm hashes block headers with double sha-256 (sha256(sha256(header))); the hash function is sha-256., bitcoin developer guide (developer.bitcoin.org): 'proof of work' section states bitcoin uses double sha-256 hashing for its proof-of-work algorithm; bitcoin wiki 'proof of work' article confirms the hash function used is sha-256., bitcoin developer guide (developer.bitcoin.org): 'the bitcoin network uses the sha-256 hash algorithm to generate verifiably random numbers in a way that requires a predictable amount of computer processing power' — the proof-of-work hash function is sha-256 (applied twice, i.e. double-sha-256)., bitcoin developer guide (developer.bitcoin.org): 'the block header hash ... is computed by running the block header through the sha256 algorithm ... bitcoin uses sha256 for both of its hash functions.' also documented in bitcoin wiki 'block hashing algorithm' and the original bitcoin whitepaper's proof-of-work section describing hashcash-style sha-256 hashing., bitcoin developer guide (developer.bitcoin.org): 'the block header's hash must be lower than or equal to the target ... generated by hashing the block header twice with sha-256'; bitcoin wiki 'proof of work' article also states bitcoin uses sha-256 for its proof-of-work hashcash function., bitcoin developer guide (developer.bitcoin.org): 'the header's hash must be lower than or equal to the target ... using sha256(sha256())' — bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256)., bitcoin developer guide (developer.bitcoin.org): bitcoin proof-of-work uses sha-256, applied twice (double sha-256) in the block header hashing algorithm., bitcoin developer guide (developer.bitcoin.org): bitcoin's proof-of-work mining algorithm uses sha-256 (specifically double sha-256) as its hash function., bitcoin developer guide (developer.bitcoin.org, 'proof of work' section) and the original bitcoin whitepaper by satoshi nakamoto, both stating bitcoin's proof-of-work uses sha-256 (specifically double sha-256) as its hash function, bitcoin developer guide (developer.bitcoin.org/devguide/block_chain.html), 'proof of work' section: bitcoin's proof of work uses sha-256, applied twice (sha256d), to the block header., bitcoin developer guide (developer.bitcoin.org/devguide/block_chain.html): 'the mining process... to create a block, miners... compute the double sha-256 hash of the block header.' widely corroborated by the original bitcoin whitepaper (bitcoin.org/bitcoin.pdf, section 4, 'proof-of-work'), which specifies the proof-of-work as scanning for a value that, when hashed with sha-256, gives a hash beginning with a number of zero bits., bitcoin developer guide (proof of work section, developer.bitcoin.org) and the bitcoin whitepaper (satoshi nakamoto, 2008, section 4), both stating bitcoin's proof-of-work uses sha-256 (double sha-256, i.e. sha-256 applied twice) as the hash function., bitcoin developer guide / bitcoin core documentation (bitcoin.org): bitcoin's proof-of-work uses the sha-256 hash function (double sha-256 in the mining hash algorithm)., bitcoin developer guide / bitcoin core documentation (bitcoin.org): bitcoin's proof-of-work uses the sha-256 hashing algorithm (specifically double sha-256) as defined in the original bitcoin whitepaper by satoshi nakamoto (bitcoin.org/bitcoin.pdf, section 4, 'proof-of-work')., bitcoin developer guide / bitcoin core documentation (bitcoin.org): bitcoin's proof-of-work uses the sha-256 hashing algorithm (specifically double sha-256, sha-256d) as defined in the original bitcoin whitepaper by satoshi nakamoto (2008)., bitcoin developer guide / bitcoin core documentation: bitcoin's proof-of-work algorithm computes a double sha-256 hash (sha256(sha256(block header))) of the block header and requires the result to be below the target; the underlying hash function used is sha-256., bitcoin developer guide / bitcoin core documentation: bitcoin's proof-of-work algorithm hashes the block header twice with sha-256 (double-sha-256), bitcoin developer guide / bitcoin core documentation: bitcoin's proof-of-work mining algorithm uses the sha-256 hash function (double sha-256, per the original bitcoin whitepaper by satoshi nakamoto, 2008)., bitcoin developer guide / bitcoin core documentation: proof of work uses double sha-256 hashing of the block header, bitcoin developer guide / bitcoin core documentation: proof-of-work uses double sha-256 (sha-256 applied twice) as the hashing algorithm for block headers, bitcoin developer guide / bitcoin protocol documentation: bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256) to hash block headers., bitcoin developer guide / bitcoin wiki (developer.bitcoin.org): bitcoin's proof-of-work uses the sha-256 hashing algorithm (double sha-256, i.e. sha256(sha256(block header)))., bitcoin developer guide / bitcoin wiki (proof of work): bitcoin's proof-of-work uses the sha-256 hash function, applied twice (sha256d) to the block header., bitcoin developer guide / bitcoin wiki - proof of work: bitcoin's mining proof-of-work uses the sha-256 hash function (double sha-256, per the bitcoin protocol specification)., bitcoin developer guide / bitcoin wiki - proof of work: bitcoin's proof-of-work algorithm is double sha-256 (sha256(sha256(block_header))), as specified in the original bitcoin whitepaper and implemented in bitcoin core., bitcoin developer guide / bitcoin wiki: 'proof of work is a piece of data ... hashing the block header twice with sha-256', bitcoin developer guide / bitcoin wiki: 'proof of work' - bitcoin's proof-of-work algorithm hashes block headers with sha-256 applied twice (double sha-256), bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work (mining) uses the sha-256 hash function, specifically double sha-256 (sha256d), as defined in bitcoin core's consensus code (satoshi's original whitepaper and implementation)., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work function is sha-256 (double sha-256, i.e. sha-256 applied twice) as specified in the original bitcoin whitepaper and implemented in bitcoin core's block header hashing., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work mining algorithm (sha256d) uses the sha-256 cryptographic hash function, applied twice to the block header., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work mining algorithm is double sha-256 (sha256d) applied to the block header, per the original bitcoin whitepaper and reference implementation (bitcoin.org/en/developer-guide#proof-of-work)., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work mining algorithm uses double sha-256 as its hash function, bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work uses double sha-256 (sha256(sha256(block_header))) as the hashing algorithm for mining, bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work uses the sha-256 hash function (double sha-256, applied to the block header)., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work uses the sha-256 hash function (double sha-256, applied twice) as specified in the original bitcoin whitepaper and reference implementation., bitcoin developer guide / bitcoin wiki: bitcoin's proof-of-work uses the sha-256 hash function, applied twice (double sha-256) to the block header., bitcoin developer guide / bitcoin wiki: block hashing algorithm (https://en.bitcoin.it/wiki/block_hashing_algorithm) — states bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256)., bitcoin developer guide / bitcoin.org: 'block headers' and 'proof of work' sections state that bitcoin mining uses the sha-256 hash function (specifically double sha-256) as its proof-of-work algorithm., bitcoin developer guide / bitcoin.org: bitcoin's proof-of-work function is sha-256 (double sha-256, sha256d), as specified in the original bitcoin whitepaper and implemented in bitcoin core's block hashing algorithm., bitcoin developer guide / wikipedia: bitcoin's proof-of-work uses the sha-256 hash function (double sha-256) as specified in bitcoin's original design (nakamoto, 2008)., bitcoin developer guide, 'proof of work' (https://developer.bitcoin.org/devguide/block_chain.html#proof-of-work); bitcoin whitepaper, section 4 (https://bitcoin.org/bitcoin.pdf)., bitcoin developer reference (developer.bitcoin.org): mining uses the double sha-256 hash function for proof of work, bitcoin developer reference / bitcoin wiki: bitcoin's proof-of-work algorithm is double sha-256 (sha256d), i.e. the hash function used is sha-256, applied twice to the block header., bitcoin developer reference / bitcoin wiki: bitcoin's proof-of-work function is double sha-256 (sha256(sha256(block_header))), commonly named as the hash function sha-256, bitcoin developer reference / bitcoin wiki: bitcoin's proof-of-work uses the sha-256 hash function (double sha-256, applied twice) on the block header., bitcoin developer reference, block chain — https://developer.bitcoin.org/reference/block_chain.html, bitcoin developer reference, block headers: https://developer.bitcoin.org/reference/block_chain.html#block-headers, bitcoin improvement proposal bip-9 / bitcoin core documentation: bitcoin's proof-of-work uses double sha-256 (sha256d), commonly referred to as sha-256., bitcoin protocol documentation (bitcoin.org developer guide / bitcoin whitepaper, satoshi nakamoto 2008) and the bitcoin core source (src/pow.cpp, src/hash.h), which define proof-of-work as double sha-256 (sha256(sha256(block header))), with the underlying hash function named sha-256., bitcoin protocol documentation (bitcoin.org developer guide / original bitcoin whitepaper by satoshi nakamoto): bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double-sha-256, to the block header)., bitcoin protocol documentation (bitcoin.org developer guide) and bitcoin core source code, which specify that bitcoin's proof-of-work uses the sha-256 hash function (applied twice, i.e. double sha-256) via the getblocktemplate / block header hashing algorithm., bitcoin protocol documentation (bitcoin.org developer reference / bitcoin whitepaper by satoshi nakamoto): bitcoin's proof-of-work uses the sha-256 hash function, applied twice (double sha-256) to the block header., bitcoin protocol documentation (bitcoin.org/en/developer-guide, 'proof of work' section) and the original bitcoin whitepaper (section 4, 'proof-of-work'), both stating bitcoin's proof of work uses the sha-256 hash function (applied twice, i.e. double sha-256) to hash block headers., bitcoin protocol documentation / bitcoin core source (bitcoin.org developer reference, 'proof of work': bitcoin uses sha-256 as its proof-of-work hash function, applied twice (double-sha-256) to the block header), bitcoin protocol documentation / bitcoin.org developer guide: bitcoin's proof-of-work mining algorithm hashes the block header twice with sha-256 (double-sha-256)., bitcoin protocol documentation / original bitcoin whitepaper (satoshi nakamoto, 2008): bitcoin's proof-of-work uses double sha-256 hashing of the block header., bitcoin whitepaper (bitcoin.org/bitcoin.pdf), section 4 'network': 'the proof-of-work involves scanning for a value that when hashed... the hash begins with a number of zero bits'; bitcoin core source (src/pow.cpp / src/hash.h) implements this proof-of-work check using sha-256 (applied twice, i.e. double-sha256) as specified in the bitcoin developer reference (developer.bitcoin.org/reference/block_chain.html)., bitcoin whitepaper (bitcoin.org/bitcoin.pdf), section 4 'proof-of-work', and the bitcoin core reference implementation, which both specify sha-256 (applied twice, i.e. double sha-256) as the hash function used for mining proof-of-work., bitcoin whitepaper (nakamoto, 2008, section 4 'proof-of-work') and bitcoin core developer documentation, both of which specify that bitcoin's proof-of-work uses sha-256 (applied twice, i.e. double-sha-256) as the hash function for block hashing., bitcoin whitepaper (satoshi nakamoto, 2008), section 4 'proof-of-work': 'the proof-of-work involves scanning for a value that when hashed, such as with sha-256...', bitcoin whitepaper (satoshi nakamoto, 2008), section 4 'proof-of-work': the proof-of-work involves scanning for a value that when hashed with sha-256 gives a hash with leading zero bits, bitcoin wiki / bitcoin protocol documentation: bitcoin's proof-of-work mining algorithm applies sha-256 twice (double-sha-256) to the block header; the underlying hash function is sha-256, as specified in the original bitcoin whitepaper (nakamoto, 2008) and bitcoin core source (src/pow.cpp, src/hash.h)., bitcoin wiki / bitcoin protocol documentation: bitcoin's proof-of-work mining algorithm uses double sha-256 hashing over the block header, commonly referred to as the sha-256 hash function., bitcoin wiki, 'proof of work' (https://en.bitcoin.it/wiki/proof_of_work) and bitcoin core source (sha256d used in block header hashing, src/pow.cpp / src/hash.h) both state bitcoin's proof-of-work uses double sha-256 (sha-256d)., bitcoin wiki, 'proof of work' / bitcoin.org developer guide: bitcoin's proof-of-work algorithm is double sha-256 (sha256d) applied to the block header; the hash function used is sha-256., bitcoin wiki, 'proof of work' and 'block hashing algorithm' articles (en.bitcoin.it), which state bitcoin's proof-of-work uses sha-256 (specifically double sha-256) as the hash function., bitcoin wiki, proof of work (https://en.bitcoin.it/wiki/proof_of_work): "the most widely used proof-of-work scheme is based on sha-256 and was introduced as a part of bitcoin.", bitcoin.org, bitcoin.org developer guide (developer.bitcoin.org): 'the header is hashed twice with sha-256'; bitcoin wiki 'proof of work' article: block header hashed with double sha-256., bitcoin.org developer guide, block chain section: 'the block header is hashed twice with sha-256'; bitcoin wiki 'proof of work' article confirms the mining proof of work uses double sha-256., developer.bitcoin.org, en.bitcoin.it, satoshi nakamoto, bitcoin: a peer-to-peer electronic cash system, section 4 proof-of-work (https://bitcoin.org/bitcoin.pdf); bitcoin developer documentation, block chain (https://developer.bitcoin.org/reference/block_chain.html)

Work

  1. pinnedblocks 26,078,021 to 26,078,320 to · on Ethereum mainnet
  2. answered149 of 149 agreed140 needed
    #729SHA-256Bitcoin Developer Guide / Bitcoin Wiki: Bitcoin's proof-of-work mining algorithm is double SHA-256 (SHA256d) applied to the block header, per the original Bitcoin whitepaper and reference implementation (bitcoin.org/en/developer-guide#proof-of-work).
    #1905SHA-256from developer.bitcoin.org
    #1032SHA-256from en.bitcoin.it
    #1735SHA-256Bitcoin Core developer documentation and the original Bitcoin whitepaper (Nakamoto, 2008, Section 4: 'Proof-of-Work'), which specify that block headers are hashed with SHA-256 (applied twice) to find a value below the difficulty target.
    #1022SHA-256Bitcoin protocol documentation (bitcoin.org Developer Guide / original Bitcoin whitepaper by Satoshi Nakamoto): Bitcoin's proof-of-work uses the SHA-256 hash function (applied twice, i.e. double-SHA-256, to the block header).
    144 more
  3. signed
    by the attester 0x5598…2982expired

    Checking the signature in this browser.

    typed data
    the exact bytes a consumer verifies, as JSON
    attester
    0x5598aa9146215bc13eb26f2c692ad1461fd32982
    signature
    0x35970b6d71bbde87276ce5a098011cf8b0f2d68302f6af5c6d3ba7e19e11097361ff8a368b7049b6c8e78978af4ee9fc02a701e854ed1b17d79effbc76b8bf621b
    question hash
    0x543a57c09ee18f4fe9d4be05ac018b958c536405fab5afafac7eb6fecdab8252
    answer type
    bytes32
    consumer
    none named; signed for the zero address
  4. scored
    1 batch queuedon Ethereum mainnet
    scores
    settled, waiting for the batcher