What is mining difficulty?
- Author
- CRYPTO PORT Editorial
- Published
- Updated
- Reading time
- 5 min
In short
Mining difficulty expresses how much computation it takes to find a valid block. The network adjusts it automatically so that blocks keep appearing at a steady pace even as total hash power rises or falls. Bitcoin recalculates it every 2,016 blocks.
Key points
- A measure of how hard it is to find a valid hash
- Adjusted automatically to keep block intervals steady
- Rises as total hash power grows
- No individual miner can change it
Definition
A figure describing how strict the target a block hash must fall below is. It moves up or down automatically, by protocol rule, whenever block intervals drift from the target.
A block is only valid if its hash falls below a target value. The smaller the target, the rarer a qualifying hash and the more attempts are needed. Difficulty expresses that strictness as a ratio against a reference point.
Bitcoin recalculates difficulty every 2,016 blocks by comparing how long those blocks actually took against the two-week target. Blocks arriving early push difficulty up; late blocks push it down. Any single adjustment is capped at a factor of four in either direction.
Because of this, the average ten-minute block interval holds even as mining hardware proliferates worldwide. For a miner it means that holding the same equipment yields a shrinking share as others join.
Watch out for
- · Difficulty can fall as well as rise when participants leave
- · Adjustments happen on a fixed block schedule and lag sudden swings in hash power
- · Each chain uses its own adjustment period and formula, so Bitcoin's rules do not transfer