What Is the Concept of “Selfish Mining” and How Does It Differ from a 51% Attack?

Selfish mining is a strategy where a miner or pool finds a new block but withholds it from the public network, secretly extending their own private chain. The goal is to gain an unfair advantage in the race to find the next block, increasing their block reward share beyond what their hashrate would mathematically dictate.

A 51% attack, by contrast, requires control of the majority hashrate and is used to actively manipulate the ledger, specifically for double-spending. Selfish mining is an attempt to gain a larger share of mining rewards, not to corrupt the ledger's integrity through a reorg.