Bitcoin Block 1

The first block after the genesis block – mined January 9, 2009

Overview

Block 1 is the very first block mined on the Bitcoin network after the hardcoded genesis block. It was mined on January 9, 2009 (timestamp: 1231469665, or 02:54:25 UTC) and contains only one transaction: the coinbase reward transaction awarding 50 BTC to the miner. Unlike the genesis block, this reward is fully spendable. It references the genesis block as its previous block hash and maintains the initial difficulty level.

View this block live on explorers:

Block Header (80 bytes)

The block header is double-SHA256 hashed to produce the block hash.

Version: 1 (0x01000000)
Previous block hash: 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
Merkle root: 0e3e2357e806b6cdb1f70b54c3a3a17b6714ee1f0e68bebb44a74b1efd512098
Timestamp: 1231469665 (January 9, 2009 02:54:25 UTC)
Bits (difficulty target): 0x1d00ffff (ffff001d in little-endian)
Nonce: 1639830024 (61bc6649 in little-endian hex)

Block Hash (double SHA-256 of header):

00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048

Coinbase Transaction (only transaction in the block)

Version: 1
Input count: 1
Input:
- Previous output: all zeros
- Output index: -1 (0xffffffff)
- ScriptSig (35 bytes): 04ffff001d0104
- Sequence: 0xffffffff
Output count: 1
Output:
- Value: 50 BTC (5,000,000,000 satoshis)
- ScriptPubKey (67 bytes): 410496b538e853519c726a2c91e61ec11600ae1390813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166bf621e73a82cbf2342c858eeac
Locktime: 0

Full serialized coinbase transaction hex (153 bytes):

01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff0704ffff001d0104ffffffff0100f2052a0100000043410496b538e853519c726a2c91e61ec11600ae1390813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166bf621e73a82cbf2342c858eeac00000000

Key Special Properties

First block to reference the genesis block (previous hash is the genesis block hash)
Only one transaction (coinbase)
The 50 BTC reward is spendable (in contrast to the genesis block)
No embedded message or newspaper headline in the coinbase ScriptSig (unlike genesis)
Difficulty remains at the starting level (same bits as genesis)
Full serialized block size: approximately 215 bytes