Free chess calculator
What was that event really worth? Enter how many games you played, the average rating of your opponents, and your score, and see the rating you performed at.
A typical weekend Swiss is 5–9 rounds.
The mean rating of everyone you faced. It anchors the whole result.
1 per win, ½ per draw. Half-points allowed.
Every clear win-over-loss across the event is worth about 400 rating points, so an even score performs at the field average and each extra point lifts you fast. This linear version tracks FIDE closely except at a perfect or zero score, where a single game can't pin an exact number — treat those as “at least”.
The single rating that would have predicted your result across an event. An even score means you performed at the field's average rating; scoring above 50% lifts your performance above it, and below drops it.
This calculator uses the linear rule of thumb: the average opponent plus 400 points for each clear win-over-loss per game. It matches FIDE's table closely except near a perfect or zero score, where a single event can't pin an exact number — there, read the result as 'at least'.
No. A performance rating describes one event. Your official rating moves game by game via the Elo change formula, which this site's Expected score & rating change calculator shows.
Your win/draw/loss odds against any opponent, and exactly what a win, draw or loss does to your rating.
Turn a rating gap into a probability and plain odds — and see why the curve is an S, not a line.
Your most likely total over N games at a given rating gap, plus the honest spread around it.
Educational chess content. Rating math uses the standard Elo model; results are estimates and vary by federation, pool and time control.