What is the Bitcoin halving?
DefinitionThe Bitcoin halving is a built-in event that cuts the reward miners receive for each new block in half every 210,000 blocks, roughly every four years. It slows the creation of new bitcoin until the 21 million limit is reached.
How the halving works
The halving works through a rule in Bitcoin’s code: every 210,000 blocks, the block subsidy, the new bitcoin paid to the miner who finds a block, is cut by 50%. No company decides it; every node enforces the same schedule automatically.
Because blocks arrive about every 10 minutes, 210,000 blocks take close to four years. The exact date depends on how fast blocks are found, so a halving is scheduled by block height, not by calendar date.
Past and next halvings
Bitcoin started in 2009 with a reward of 50 BTC per block. Since then the reward has been halved four times:
- November 2012, block 210,000: from 50 to 25 BTC
- July 2016, block 420,000: from 25 to 12.5 BTC
- May 2020, block 630,000: from 12.5 to 6.25 BTC
- April 2024, block 840,000: from 6.25 to 3.125 BTC
- Next, expected around 2028 at block 1,050,000: from 3.125 to 1.5625 BTC
What the halving means
The halving halves the rate at which new bitcoin is created, which is why the supply approaches 21 million so slowly; the last fractions are expected to be mined around the year 2140. After that, miners will rely entirely on transaction fees.
People often link halvings to price cycles, but past patterns are not a reliable guide and many other factors move the market. A halving does not change the bitcoin you already hold, and you don’t need to do anything in your wallet.
Other coins with halvings
Litecoin follows Bitcoin’s model with a halving every 840,000 blocks, also about every four years; its most recent one was in August 2023. Dogecoin has no halving: since 2015 it has paid a fixed 10,000 DOGE per block, so its supply keeps growing.
