In plain English
What Bitcoin halving means
Bitcoin pays miners a block subsidy for adding valid blocks. Roughly every four years, after 210,000 blocks, that subsidy is reduced by 50%. The halving is built into the protocol and is part of Bitcoin’s fixed issuance schedule.
Why it matters
The halving is central to Bitcoin’s supply path and miner revenue. It lowers new issuance over time, so the balance between block subsidy, transaction fees, and mining costs becomes more important after each event.
Example
If a block subsidy were 6.25 BTC before a halving, it would become 3.125 BTC after the next one. That is a simplified arithmetic example; the exact subsidy depends on the current era in the protocol.
Quick answers
Common questions
How often does Bitcoin halve?+
About every 210,000 blocks, which is roughly every four years, though the exact calendar timing varies with block production.
Does the halving change existing bitcoins?+
No. It changes the rate of new issuance, not the balance of coins already in circulation.
Sources