Halving
Also · Halvening
The halving cuts the number of new bitcoins created per block in half every 210,000 blocks, roughly every 4 years. The last one, in April 2024, set the subsidy at 3.125 BTC.
The block subsidy started at 50 BTC in 2009. Every 210,000 blocks, which at 10 minutes a block is close to 4 years, the consensus rules halve it. It fell to 25 BTC in 2012, 12.5 in 2016, 6.25 in 2020 and 3.125 in April 2024. The series ends around the year 2140, when the subsidy rounds down to 0.
The halving reduces the flow of new coins, not the fees, which keep paying miners on top of the subsidy. Its market effects are debated and depend on expectations, liquidity and mining profitability. Its monetary effect is not debated. It is the mechanism that makes the 21 million cap a schedule rather than a promise.
In French · Halving