21 BTCHalving
Every 210,000 blocks, roughly every four years, the number of new bitcoins paid to miners per block is cut in half. This is how Bitcoin's supply is capped at 21 million.
Short definition
Every 210,000 blocks the new-coin reward per block halves. Next: block 1,050,000 (3.125 → 1.5625 BTC).
Schedule
- Block 0 (2009): 50 BTC per block
- Block 210,000 (28 Nov 2012): 25 BTC
- Block 420,000 (9 Jul 2016): 12.5 BTC
- Block 630,000 (11 May 2020): 6.25 BTC
- Block 840,000 (20 Apr 2024): 3.125 BTC
- Block 1,050,000 (expected 2028): 1.5625 BTC
The subsidy is an integer number of satoshis halved (rounded down) at each step, so it reaches zero after 33 halvings, around the year 2140. Miners will then earn only fees.
Halvings and price cycles
Past halvings were followed by large bull markets, which gave rise to the four-year-cycle idea. Four data points are not proof; the Cycles page shows them side by side on real price history.
From the Bitcoin Museum
First halving (block 210,000) (28 Nov 2012): The block reward falls from 50 to 25 BTC at 15:24 UTC.
Second halving (block 420,000) (9 Jul 2016): The reward falls from 25 to 12.5 BTC at 16:46 UTC.
Third halving (block 630,000) (11 May 2020): The reward falls from 12.5 to 6.25 BTC at 19:23 UTC.
Fourth halving (block 840,000) (20 Apr 2024): The reward falls from 6.25 to 3.125 BTC at 00:09 UTC.
See also
- 21 million supply capThere will never be more than 21 million bitcoins. Over 95% are already issued; the rest trickles out with each block until about 2140.
- MiningMining is the work that adds new blocks to Bitcoin. Miners run special computers (ASICs) that guess numbers; the winner of each round earns the block subsidy and the fees.
- BlockA block is a batch of Bitcoin transactions added to the chain about every ten minutes. The miner who finds it collects the new coins and the fees.
- Difficulty adjustmentEvery 2,016 blocks (about two weeks) Bitcoin makes mining harder or easier so that a block still arrives about every ten minutes on average.
References
- Bitcoin Core source: GetBlockSubsidy (validation.cpp) github.com
- Block 840,000 on mempool.space mempool.space
- Bitcoin Wiki: Controlled supply en.bitcoin.it
- mempool.space mempool.space
- mempool.space mempool.space
- mempool.space mempool.space