Bitcoin halvings

Every 210,000 blocks, Bitcoin's block subsidy halves. Four halvings have completed; about 30 more sit in the schedule before the subsidy integer-shifts to zero and the network must run on fees alone, somewhere around the year 2140.

Next halving
Block 1,050,000
3.125 BTC → 1.5625 BTC
100,821
blocks remaining
693
days, estimated
Projected ETA (UTC)
2028-04-05T18:02:40+00:00
via 9.9-min avg block interval
Epoch 4 progress · block 840,000 → 1,050,000 51.99% complete
Tip is at block 949,179, 109,179 blocks into this epoch. Current block subsidy: 3.125 BTC per block.

Completed halvings

Block heights and timestamps are verified against our own bitcoind via getblockheader. Block hashes are deterministic and can be re-checked at any full-node explorer.

# Block height Date (UTC) Subsidy change BTC issued in epoch % of 21M Cumulative supply
1 210,000 2012-11-28T15:24:38Z 50.0 → 25.0 BTC 5,250,000 25.000% 15,750,000 BTC
2 420,000 2016-07-09T16:46:13Z 25.0 → 12.5 BTC 2,625,000 12.500% 18,375,000 BTC
3 630,000 2020-05-11T19:23:43Z 12.5 → 6.25 BTC 1,312,500 6.250% 19,687,500 BTC
4 840,000 2024-04-20T00:09:27Z 6.25 → 3.125 BTC 656,250 3.125% 20,343,750 BTC

Supply curve through 2140

Cumulative BTC supply by block height. The classic stepped-asymptote shape, computed from the halving schedule. Halving events marked. Right edge approaches the 21M cap but never crosses it; the integer subsidy reaches zero around block 13.4M (~2140) and issuance stops.

Miner revenue: fees as a share of total

The chart that actually matters for Bitcoin's long-term security: how much of miner revenue comes from transaction fees vs the block subsidy, monthly-averaged. The subsidy halves every four years; the fee share must climb to 100% by 2140 (or much sooner if the network can't sustain miners on the smaller subsidy). Halving events marked.

944,061 blocks indexed.

Projected halvings

ETAs derived from the actual recent block-interval average (9.90 min), not the protocol target of 10 min. Real mainnet runs slightly faster than target in most epochs, so projections drift earlier than naive 10-min math.

# Block height Projected date (UTC) Subsidy change BTC issued in epoch % of 21M
5 1,050,000 2028-04-05T18:02:40+00:00 3.125 → 1.5625 BTC 328,125.0000 1.5625%
6 1,260,000 2032-03-20T05:10:57+00:00 1.5625 → 0.78125 BTC 164,062.5000 0.7812%
7 1,470,000 2036-03-03T16:19:14+00:00 0.78125 → 0.390625 BTC 82,031.2500 0.3906%
8 1,680,000 2040-02-16T03:27:32+00:00 0.390625 → 0.1953125 BTC 41,015.6250 0.1953%
9 1,890,000 2044-01-30T14:35:49+00:00 0.1953125 → 0.09765625 BTC 20,507.8125 0.0977%
10 2,100,000 2048-01-14T01:44:06+00:00 0.09765625 → 0.04882812 BTC 10,253.9052 0.0488%
11 2,310,000 2051-12-28T12:52:23+00:00 0.04882812 → 0.02441406 BTC 5,126.9526 0.0244%
12 2,520,000 2055-12-12T00:00:41+00:00 0.02441406 → 0.01220703 BTC 2,563.4763 0.0122%
13 2,730,000 2059-11-25T11:08:58+00:00 0.01220703 → 0.00610351 BTC 1,281.7371 0.0061%
14 2,940,000 2063-11-08T22:17:15+00:00 0.00610351 → 0.00305175 BTC 640.8675 0.0031%

Why halvings matter

Bitcoin's monetary policy is the only one in financial history that's fully known in advance, fully deterministic, and fully enforced by the network rather than a central authority. Halvings are the visible expression of that policy. Each one cuts the rate of new BTC issuance in half. The supply curve above is unavoidable given the rules; the only variable is when each block lands, which is itself bounded by the difficulty adjustment.

The interesting open question, plotted in the second chart above, is whether transaction fees alone can sustain network security as the subsidy approaches zero. Today fees are a small percentage of total miner revenue; by 2140 they must be 100%. The trajectory between now and then is what every Bitcoin Core developer, miner, and long-term holder is implicitly betting on.