Difficulty adjustment
The difficulty adjustment is the automatic recalibration of mining difficulty every 2,016 blocks, keeping the 10-minute block interval stable regardless of network hashrate.
Perhaps Satoshi's most brilliant design: a self-regulating mechanism always enforcing ~10-minute blocks. Every 2,016 blocks (~2 weeks) the network compares actual block time to the 20,160-minute target. Too fast? Difficulty rises. Too slow? Falls. Maximum adjustment: 4× per retarget (up or down).
Example
During the China mining ban in 2021, 50% of hashrate left the network. Within two retargets difficulty dropped 46% — blocks temporarily took 15+ minutes before the pace returned.
Frequently asked questions
Why exactly 2,016 blocks?
2,016 blocks × 10 minutes = 20,160 minutes = 14 days. A period long enough for stability, short enough for responsiveness.
Related terms
Further reading
- → Our service: Bitcoin sector