Coinbase Transaction
Mining● Common
The first transaction in every block, created by the miner to claim the block reward (subsidy + fees). Has no inputs in the traditional sense; instead contains a 'coinbase' field where miners can include arbitrary data (up to 100 bytes). Outputs are unspendable for 100 blocks (coinbase maturity).
Technical Notes
Input txid is all zeros, vout is 0xFFFFFFFF. Coinbase field must be 2-100 bytes. First bytes typically contain block height (required since BIP-34). Satoshi embedded 'The Times 03/Jan/2009' headline in genesis block coinbase. Block reward halves every 210,000 blocks.
Metadata
Visibility: Public
Created:1/3/2026by System