21 Million

Bitcoin's monetary policy is simple: there will only ever be 21 million bitcoin. New coins are issued to miners through the block subsidy, and that subsidy is cut in half roughly every four years.

Who Enforces The Cap

The cap is not enforced by miners, exchanges, foundations, or social agreement alone. Full nodes enforce it by rejecting blocks that create more bitcoin than the rules allow.

If a miner tries to pay itself too much, nodes reject the block. The miner wasted energy and receives nothing from users following the valid chain.

Halvings

Every 210,000 blocks, the subsidy drops by half. This schedule started at 50 BTC per block and trends toward zero. Fees remain as the long-term payment to miners for including transactions.

The important part is not the calendar date. The important part is that issuance is rule-bound and independently verifiable.

Scarcity Needs Verification

Scarcity is only meaningful if users can verify it. Running a node lets you verify supply, transaction validity, and the chain you are using. Without verification, you are trusting someone else's view of Bitcoin.

Common Confusion

Bitcoin can be divided into 100 million satoshis per bitcoin. Divisibility does not inflate supply. Cutting a pizza into more slices does not create more pizza.