supply

Bitcoin's total supply is capped at 21 million coins. This limit is written into the Bitcoin protocol and enforced by every node that participates in the network. No authority, no miner, and no developer can create bitcoin beyond this cap. New bitcoin enters circulation only through mining, and the rate at which it is created decreases on a fixed schedule through events called halvings. Approximately every four years, the block reward given to miners for finding a new block is cut in half. This process continues until around the year 2140, when the last fraction of a bitcoin will be mined and the total supply reaches its absolute ceiling.

The controlled issuance schedule means Bitcoin's inflation rate is transparent and predictable. Unlike fiat currencies, where central banks can expand the money supply at will, Bitcoin's monetary policy cannot be changed by any individual or committee. As of early 2024, more than 93 percent of all bitcoin that will ever exist has already been mined. The remaining supply will be released slowly over the coming century, with each halving reducing the pace further. After the 2024 halving, miners receive 3.125 bitcoin per block, down from 6.25 before, and from 50 when Bitcoin launched in 2009.

The fixed supply is central to how many people understand Bitcoin's value proposition. Scarcity is a property that cannot be replicated by a competing cryptocurrency without starting from the same social consensus. Any new cryptocurrency can copy Bitcoin's code and set a cap on its own supply, but that cap carries no equivalent weight unless users and economic participants broadly choose to treat it as meaningful. Bitcoin's supply cap has been maintained continuously since its launch, and altering it would require every node operator and miner in the world to agree, an effectively impossible threshold given the globally distributed and largely anonymous nature of participation.