Block Height

Block height is the position of a block in the blockchain, counted as the number of blocks between it and the genesis block, which sits at height 0. The bitcoin chain passed height 800,000 in July 2023, and height advances by one roughly every 10 minutes as each new block is mined.

Why it matters

Height is Bitcoin's native clock. The protocol schedules its most important events by block count rather than calendar time: the block subsidy halves every 210,000 blocks, difficulty adjusts every 2,016 blocks, and newly mined coins become spendable only 100 blocks after creation. Timelocked transactions and soft fork activations are also commonly specified by height, because block numbers cannot be faked or drift the way timestamps can. When people cite the moment of a halving or an upgrade, they cite a height, such as the fourth halving at block 840,000 in April 2024.

In the gold vs bitcoin debate

Block height makes bitcoin's monetary schedule legible in a way gold's can never be. Gold's future supply depends on mining economics, ore discoveries, and technology, and annual production near 3,000 tonnes can rise or fall with the gold price. Bitcoin's issuance at any future height is known exactly today: anyone can state precisely how many coins will exist at height 1,050,000. That deterministic schedule, indexed by height, is the core of the digital scarcity argument.