How the skill rating works

Every player starts on 1500. For each finished game, the two sides are compared on their average rating, that comparison gives an expected result, and the points that change hands are the gap between the expected result and what actually happened.

Nothing moves while a session is live. Ratings are worked out when the session ends, going through its games in the order they were played. An offline session counts once it has been sent to the club.

You have one rating per sport, wherever you play it. A club session, a cross-club session and a game at another venue all feed the same number. Badminton and padel are never mixed: a padel result does not touch your badminton rating. In badminton, doubles and singles are rated separately: the headline is your doubles rating, and singles games move a singles rating of their own. Padel is always doubles, so it has one rating.

The rating reads only who won. What a single result is depends on the sport and on the match length chosen when the session started.

Best of 3 and best of 5 are only offered with normal scoring in an open club session. Americano and Mexicano rounds, round-robin sessions and sessions entered afterwards always play one game or one set per match.

Padel records the games of each set, not the points inside them, so whether a club plays golden point or advantage makes no difference to what is stored or to the rating.

Each player has a reliability: how sure the rating is about them. It starts at 0% for a newcomer, climbs with every badminton game or padel set they play (about 63% after ten, 95% after thirty) and drifts back down when they stop playing, because the experience behind it halves for every 90 days without a rated game. The step size follows it. A brand-new player moves 40 points for a complete surprise, a fully settled player 18.

Each player moves by their own step, not a court average, so a newcomer partnering a regular takes the bigger share of the same result. A result against players who are still settling in counts a little less for you: from 60% of a normal game when the other side is brand new, up to 100% against settled opponents. The less sure the rating is about them, the less their result says about you.

Reliability measures how much the rating has been tested, not how good the player is. A returning player with a solid rating from last year is treated as less certain simply because a year has passed; a few sessions back on court restore it.

A doubles game has one result and four players, so the calculation has to decide who the result belongs to. It belongs to the pair, in badminton and padel alike.

1. Each side's strength is the average of its two players' ratings going into the game, after every earlier game has counted.
2. The expected result comes from comparing those two averages.
3. Both players on a side are judged against the same expectation; each then moves by their own step size, scaled by how settled the opponents are.

There is no attempt to credit one partner more than the other for the play itself. A 1700 player and a 1300 player on the same side face the same expectation, whoever carried the game, because the score cannot say.

Someone who has never played starts on 1500 with no reliability. Their first results move them quickly, and results against them count less for their opponents until they have settled.

The calculation uses each player's rating going into the game. Team balance, when an organiser turns it on, compares the ratings players had when they joined the session instead, so the two can differ late in a long session.

Your pair averages 1490. The pair across the net averages 1580. All four of you have about fifteen games or sets behind you, so every rating is fairly settled (reliability around 78%).

The numbers are the same in both sports because only the result counts. Beating the stronger pair is worth more than beating an equal one, and losing narrowly to a stronger pair still costs points: a close score is no consolation. These figures are computed by the same function the app runs when a session ends, not typed into this page, so they cannot drift from the engine.

There is no separate club rating, venue rating or city rating. Every rated game you play in a sport, at your club, in a cross-club session or at a venue you visit, moves the same number, and each board is a list of the players who have played enough there recently. Your place can differ from board to board because the company differs, not because the number does.

Ratings only compare people who are connected by games. Two groups that never meet are each consistent inside but cannot be compared with each other until players start mixing. A 1650 in one town and a 1650 in another mean the same thing only once enough games link the two.

When the formula itself changes, every rating is rebuilt from the full history under the new rules rather than carried over, so no rating depends on which version was in use on the day.

See also Seasons, the points race and awards · Achievements overview