The highest rating any chess program holds

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3,650 Elo

Held by Stockfish 19 64-bit 4CPU. Set 2026-09-23, and has stood for 6 days. Written down here 2026-09-25.

In 1993 it was still an open question whether a machine could play chess better than any person, and the answer was four years away. It is now so thoroughly closed that nobody runs the experiment: the programs at the top of this list have not lost a serious game to a human being in two decades, and the only opponents left that can tell them apart are each other. This is what a frontier looks like after it has been crossed - a club of volunteers playing millions of games between programs on a fixed machine and a fixed clock, because that is the only remaining way to measure the difference. Two cautions belong on the figure rather than in a footnote. It is a rating and not a score: it says how often a program beats the pool it sits in, the pool is other engines of the same era, and a number produced that way is not comparable to a human player's. And because the ratings are recomputed from the whole game record each time the list goes up, this figure can fall as well as rise without anybody's program having got worse - which is the honest difference between a rating and a record, and the reason it is worth watching a rating at all. The program at the top is open source, and has been for most of the list's history, which is the other thing 1993 would not have guessed.

That description was written when this frontier was opened, on 2026-09-17, and is never rewritten. Where it and the number above it disagree, the number is the reading and the description is history.

What counts
The largest figure in the Elo column of the CCRL 40/15 Complete list - the club's own long time control, not its blitz, Chess960 or archive lists. The list is ranked on that column, so the largest figure is the top row, but the reading is taken by sorting the whole column and never by trusting the rank. Two things belong on the number rather than under it. The ratings are recomputed over the entire game database every time the list is published, so a figure can change without the program it belongs to having played; and the scale is a position within this pool of programs, on this hardware, at this clock. It is not the scale human players are rated on and the two must never be set against each other.
What moves it
The club republishes the list with a larger figure at the top of the Elo column than the one last recorded here. Games are added continuously rather than to a conference calendar, so this can move in any week.

Where to check it: https://computerchess.org.uk/4040/

The program reads it from https://computerchess.org.uk/4040/rating_list_all.html, which is the same figure in a form a script can parse.

Every reading, oldest first

Last checked: 2026-09-29

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