I counted every move of 91 million chess games. Here's what I learned.

SudoAI — Tue, 15 Sep 2026 02:33:59 +0000

Search "how many moves are in a chess game" and every page gives you a different number - usually with no source at all. So we stopped Googling and started counting.

We read 347,741 over-the-board tournament games (relayed from electronic boards over the past year) and 91.9 million rated games played on Lichess in August 2026. For every game we counted the moves, read the result, and - where the clocks were recorded - measured how much time the players actually used.

A few things surprised me:

1. A classical game is almost always 41 moves and 3 hours.

The median over-the-board classical game is 41 moves and, at 90 minutes + 30s increment, burns 3 hours 3 minutes across both clocks. Half of games pass move 40; only 14.5% pass move 60.

2. Game length barely depends on strength.

From 1400 to 2600+, the median classical game is 40-42 moves in every rating band. What changes with strength is the ending: draws go from 20.4% (1400-1599) to 60.6% (2600+), and checkmates collapse from 28.3% to 0.8% - strong players resign lost positions instead of playing them out.

3. Online is a different game.

Lichess bullet and blitz games last a median of 32 moves; rapid, 30. Half of all bullet games are decided on the clock, not the board. And in August 2026, Lichess players got checkmated by Fool's Mate 733 times.

4. Tournament rules leave fingerprints in the data.

Draws nearly double from move 29 to move 30 (1,140 to 1,992) and stay high on move 31 - exactly the shape a "no draw agreement before move 30" rule produces.

Why this matters practically: the scoresheet.

A 60-move scoresheet holds the whole game 85.5% of the time. One classical game in seven needs a second sheet. An 80-move sheet holds 97%.

That detail is the reason this study exists: we build ScanChess, a tool that turns a photo of a paper scoresheet into a replayable, analyzable PGN. Knowing how often a game spills onto a second sheet tells us what club players actually deal with at the board every week.

The full study is here - methodology, every rule we applied, and all the tables:

How Long Is a Chess Game? Moves and Minutes From 91 Million Games: https://scanchess.com/blog/how-long-is-a-chess-game

All data is downloadable as CSVs under CC BY-SA 4.0. I'd love to hear what else the numbers say to you - especially the move-60 spike, which we still can't explain.

DEV Community: SudoAI

I counted every move of 91 million chess games. Here's what I learned.