Bitcoin Reaches 20 Million Mined Coins, Enters Final Stretch

Bitcoin's finite supply has reached an important milestone, with approximately 20 million coins already mined. This leaves just over 1 million coins to be issued before the protocol reaches its 21 million supply cap in around 2140.

The halving mechanism controls the rate of new supply entering circulation over time. Every four years, the mining reward is cut in half, reducing the rate of new issuance by exactly half. The most recent halving occurred in April 2024, reducing the block reward from 6.25 to 3.125 BTC per block.

Not all finite supply tokens rely on Bitcoin's halving model. Ethereum, for example, introduced a burn mechanism through EIP-1559 in August 2021. This upgrade destroys a portion of transaction fees with every block processed, creating temporary deflation and variable supply trajectory.