How a payment works

On 12 January 2009, in block 170, 10 bitcoin moved from the key that had mined block 9 to a new key. Hal Finney later wrote that he “was the recipient of the first bitcoin transaction, when Satoshi sent ten coins to me as a test.” The payment is still in the record for anyone to check.

Live from the chain

Block 170 todayLoading live figures…

Confirmations

…its own block and every block since

Newest block

…

A payment's own block is its first confirmation, and every later block adds one. Each one makes it harder to undo, because undoing it would mean redoing the work of every block since. For a payment buried this deep, that is out of reach. For a brand-new payment, it is why many services wait for several confirmations, often around six, before treating larger amounts as settled.

See it on satoshis.watch →

What happened, step by step

1. Block 9, 9 January 2009. A miner, generally taken to be Satoshi, is paid 50 new bitcoin for the block.
2. Block 170, 12 January 2009. Those 50 bitcoin are spent in one transaction: 10 go to the new key and 40 come back to the sender as change.
3. Block 92,240, 16 November 2010. The 10 coins move on, all in one payment.

Every payment works this way

Bitcoin doesn't keep balances like a bank account. It keeps pieces: each payment you received is a separate piece, called an unspent output. To pay someone, your wallet spends whole pieces and sends whatever is left over back to you as change, usually to a new address of yours. A wallet adds all your pieces together to show your balance.

In 2009 payments went straight to public keys, with no address. Explorers show each key as the 1 address made from it: the sending side as 12cbQLTF… and Hal's side as 1Q2TWHE3…, both on satoshis.watch. Both still receive small payments from people who visit them.