How Often Does Bitcoin’s Difficulty Adjustment Occur?

Bitcoin's difficulty adjustment occurs approximately every two weeks, specifically after every 2,016 blocks are mined. The protocol calculates the actual time taken to mine the last 2,016 blocks.

If the time was less than the target of two weeks (20,160 minutes), the difficulty increases. If it took longer, the difficulty decreases.

This predictable schedule maintains the 10-minute block time average.