93% of all Bitcoin is already mined. Here’s what that means

Bitcoin’s total supply is capped at 21 million, a fixed limit enforced by its protocol. As of May 2025, approximately 19.6 million BTC have been mined (93.3% of the total), leaving roughly 1.4 million yet to be created. This uneven distribution stems from Bitcoin’s halving events, which halve the block reward every four years. The initial large rewards resulted in over 87% of the supply being mined by the end of 2020. Subsequent halvings drastically reduce the mining rate; 99% of all Bitcoin will be mined by 2035, with the final fraction mined around 2140. This engineered scarcity is a key factor in Bitcoin’s value proposition.

However, the available supply is less than the mined supply. A significant portion, estimated at 3.0 to 3.8 million BTC (14%-18%), is lost due to forgotten passwords, misplaced wallets, etc. This “lost” Bitcoin permanently reduces the circulating supply, potentially to 16-17 million BTC. This contrasts with gold, where almost all mined gold remains in circulation. Bitcoin’s non-recoverable nature creates a “hardening scarcity,” where the supply not only stops growing but also shrinks.

Concerns about the network’s security as block rewards diminish are unfounded. Bitcoin’s mining economy is self-correcting. If mining becomes unprofitable, miners leave the network, triggering a difficulty adjustment that lowers the cost for remaining miners. This mechanism ensures the network’s stability even with reduced rewards. The 2021 China mining ban demonstrated this resilience; the hashrate dropped significantly but recovered quickly. Profitability, not the absolute reward, determines mining activity. Even with near-zero block rewards in the distant future, the network will likely remain secure.

The misconception that rising Bitcoin prices will lead to endless energy consumption is also incorrect. Shrinking rewards incentivize miners to use cheaper, cleaner energy. The migration of mining operations to regions with abundant renewable energy sources demonstrates this trend. Regulations further incentivize clean energy mining. Bitcoin’s self-regulating mechanisms, including difficulty adjustments, also limit energy expansion despite price increases. The future of Bitcoin mining is increasingly likely to be powered by renewable energy sources.