Blockchain

Nonce

A throwaway number miners change over and over while hunting for a hash that meets the target.

Nonce is short for 'number used once.' In mining, it's the one part of a block a miner is free to vary. They plug in a value, hash the block, check whether the result clears the difficulty target, and if not, try the next one.

Finding a valid nonce can take quintillions of attempts, which is exactly the point: it proves real effort. The winning nonce ships inside the block so anyone can verify the solution in a single hash.

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