Bitcoin's supply is set by a simple schedule in the software: each block pays a subsidy that started at 50 BTC and halves every 210,000 blocks, rounded down to whole satoshis. Add those up and issuance ends just under 21 million BTC. The chart below is calculated from that schedule, with today's block height from mempool.space.
Source: Bitcoin Core: src/validation.cpp: GetBlockSubsidy, 50 BTC halved every 210,000 blocks, Bitcoin Core: src/consensus/amount.h: COIN (100,000,000 satoshis) and MAX_MONEY (21 million BTC).
Bitcoin issued by block height
Dashed lines mark the first five halvings, every 210,000 blocks.
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Calculated on this page from the issuance schedule. Current block from mempool.space. Dates after today are estimates at 10 minutes per block, not forecasts of anything else.
The halvings so far
| Halving | Block | Date (UTC) | Subsidy after |
|---|---|---|---|
| First | 210,000 | 28 November 2012 | 25 BTC |
| Second | 420,000 | 9 July 2016 | 12.5 BTC |
| Third | 630,000 | 11 May 2020 | 6.25 BTC |
| Fourth | 840,000 | 20 April 2024 | 3.125 BTC |
| Fifth | 1,050,000 | Estimate loading | 1.5625 BTC |
The maths, in brief
There are 33 eras of 210,000 blocks in which the subsidy is at least one satoshi. In era 0 it is 5,000,000,000 satoshis (50 BTC). In each later era it is the previous figure halved and rounded down. The last block with a subsidy is block 6,929,999. Summing every era gives 2,099,999,997,690,000 satoshis, which is 20,999,999.9769 BTC.
Source: Bitcoin Core: src/validation.cpp: GetBlockSubsidy, 50 BTC halved every 210,000 blocks, Bitcoin Core: src/consensus/amount.h: COIN (100,000,000 satoshis) and MAX_MONEY (21 million BTC), Bitcoin Core: src/kernel/chainparams.cpp: halving interval of 210,000 blocks, 10 minute block target, two week retarget, genesis block.
The supply schedule is a fact about the software. It says nothing about price, and this page does not either. For how a company might size an allocation, see the sizing guide. For what a halving means for a company, and why a four-year price cycle is a weak basis for treasury decisions, see the bitcoin halving and the four-year cycle.
Sources
Primary sources only. Each link was checked on 29 October 2026. Rules change, so confirm the current version with your adviser.
- Bitcoin Coresrc/validation.cpp: GetBlockSubsidy, 50 BTC halved every 210,000 blocks
- Bitcoin Coresrc/consensus/amount.h: COIN (100,000,000 satoshis) and MAX_MONEY (21 million BTC)
- Bitcoin Coresrc/kernel/chainparams.cpp: halving interval of 210,000 blocks, 10 minute block target, two week retarget, genesis block
- mempool.spaceBlock 210,000, the first halving (28 November 2012)
- mempool.spaceBlock 420,000, the second halving (9 July 2016)
- mempool.spaceBlock 630,000, the third halving (11 May 2020)
- mempool.spaceBlock 840,000, the fourth halving (20 April 2024)
- mempool.spaceREST API documentation: block height, hash rate, difficulty adjustment and fee estimates
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