How many blocks typically separate Bitcoin’s programmed mining-reward halvings?

Bitcoin’s programmed mining-reward halvings are typically separated by 210,000 blocks.

Bitcoin’s protocol reduces the subsidy paid to miners after every 210,000 blocks. Because Bitcoin targets an average block interval of about 10 minutes, one interval is designed to last roughly four years, although actual calendar timing varies with mining conditions.

The first halving occurred in November 2012, reducing the subsidy from 50 bitcoins to 25. Later halvings reduced it to 12.5, 6.25, and 3.125 bitcoins. The schedule continues until the subsidy becomes negligible and transaction fees provide the main incentive for miners.

The interval is measured in blocks, not years. This distinction matters because Bitcoin’s difficulty-adjustment system keeps the long-term block target near 10 minutes, while individual blocks can arrive much sooner or later. The 210,000-block rule is part of Bitcoin’s monetary issuance schedule, not a statement about the exact date of each halving.