September 2, 2020:This version of Stockfish plays significantly stronger than any of its predecessors. In a match against Stockfish 11, Stockfish 12 will typically win at least ten times more game pairs than it loses.

Powerful Stockfish is one of the strongest chess engines in the world. It is also much stronger than the best human chess grandmasters. View CCRL rating list

Open Source Stockfish is open source (GPL license). That means you can read the code, modify it, contribute back, and even use it in your own projects. Stockfish on GitHub