To elaborate, in the Top Chess Engine Championship (which is also used as a benchmark in the AlphaZero vs Stockfish comparison) Stockfish has won all seasons s

To elaborate, in the Top Chess Engine Championship (which is also used as a benchmark in the AlphaZero vs Stockfish comparison) Stockfish has won all seasons since May 2020[1,2]. A common runner up for those seasons is LCZero[3], which is an engine that is derived from/a reimplementation of AlphaZero. Stockfish is also ahead of LCZero in Fischer random chess (as hosted at TCEC) winning 4 out of the 5 FRC tournaments. As for how close Stockfish 8 is to a current version of Stockfish, Stockfish 15 has ~400 more ELO than Stockfish 8 as measured in their own self-tests[4]. However, when making these comparisons between AlphaZero and Stockfish it might be tempting to frame it as machine-learning-engine vs classical-engine, which is not true. Stockfish incorporates a neural network when evaluating chess positions[5]. [1]: https://en.wikipedia.org/wiki/Top_Chess_Engine_Championship#Tournament_results https://en.wikipedia.org/wiki/Top_Chess_Engine_Championship#... [2]: https://en.wikipedia.org/wiki/Stockfish_(chess)#Top_Chess_Engine_Championship https://en.wikipedia.org/wiki/Stockfish_(chess)#Top_Chess_En... [3]: https://en.wikipedia.org/wiki/Leela_Chess_Zero https://en.wikipedia.org/wiki/Leela_Chess_Zero [4]: https://github.com/glinscott/fishtest/wiki/Regression-Tests#fishtest-progression https://github.com/glinscott/fishtest/wiki/Regression-Tests#... [5]: https://stockfishchess.org/blog/2020/introducing-nnue-evaluation/ https://stockfishchess.org/blog/2020/introducing-nnue-evalua...