Halving
A halving is the scheduled cut, every 210,000 blocks, in the number of new bitcoins created with each block.
Photo: “Cut off” by hernanpba, CC BY-SA 2.0, via Flickr (edited: cropped and resized).
A halving is the moment Bitcoin’s block subsidy — the new coins a miner may create per block — drops by half. It happens every 210,000 blocks under a rule in Bitcoin’s software [1]. The subsidy began at 50 BTC and is 3.125 BTC since 2024 [2].
Key points
- 1Triggered by block height, not by date.
- 2Only the subsidy halves; transaction fees do not.
- 3The repeated halvings cap total issuance just under 21 million BTC.
How does a halving work?#
Every block includes a coinbase transaction that pays the miner the block reward: the block subsidy plus the fees of included transactions [3]. Bitcoin Core sets the halving interval for the subsidy at 210,000 blocks [1]. When the chain reaches heights 210,000, 420,000, 630,000 and so on, the allowed subsidy is cut in half.
| Step | Value |
|---|---|
| Blocks 0 – 209,999 | 50 BTC |
| Blocks 210,000 – 419,999 | 25 BTC |
| Blocks 420,000 – 629,999 | 12.5 BTC |
| Blocks 630,000 – 839,999 | 6.25 BTC |
| Blocks 840,000 – 1,049,999 | 3.125 BTC |
Each value is half the one before it, which is why total issuance converges just below 21 million [2].
Does a halving affect the price?#
The protocol only changes how many new coins are created. Any effect on price depends on demand and on the decisions of holders and miners, and four past halvings are too few to establish a dependable pattern. Read the full guide: Bitcoin halving explained.
Which words are related?#
- Satoshi — the smallest unit, 0.00000001 BTC.
- Block height — the block number that triggers each halving.
- Hash rate — the total mining power securing the network.
Frequently asked questions#
How often does a halving happen?
Every 210,000 blocks, which has historically worked out to roughly four years [2].
Is “halvening” the same thing?
Yes. It is an informal name for the same event.
Do all cryptocurrencies have halvings?
No. Some coins copied Bitcoin’s schedule with their own parameters; others have no fixed cap — ethereum.org describes Ether’s supply as dynamic, with new ETH issued to validators and some burned with each transaction [4]. Check each network’s own documentation.
Sources#
Grade A = primary source (regulator, protocol specification, client code, original author). Grade B = expert secondary source used for explanation only.
- ABitcoin Core (GitHub). src/kernel/chainparams.cpp (nSubsidyHalvingInterval), 2026.
- BBitcoin Wiki. Controlled supply, 2026.
- Abitcoin.org developer documentation. Bitcoin Developer Glossary: Block reward, 2026.
- Aethereum.org. What is Ethereum?, 2026.