Block Structure in the Bitcoin Blockchain


  • Block Header (an 80-byte serialized structure)
    • Version - the version of the current block format (4 bytes)
    • Hash of the previous block (32 bytes)
    • Data hash, or Merkle tree root hash (32 bytes)
    • Timestamp (4 bytes)
    • Current difficulty target (4 bytes)
    • Nonce (4 bytes)
  • Block Data
    • Transaction counter
    • Transactions #1, #2, #3, …, #n


Sample Bitcoin Blockchain