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Chess rating calculator for FIDE and UKD ratings

This chess rating calculator shows how a tournament changes your rating: enter your rating and each game’s opponent and score, and it works out the FIDE (Elo) change by the FIDE Rating Regulations or the Turkish national rating (UKD) change by the Turkish Chess Federation’s procedure. It is free and stores nothing.

Calculate your rating change

Choose FIDE or UKD, enter your rating before the tournament and one row per game. The result shows every step, so you can check it against the rules below.

Rating system

Your rating before the tournament, 1000 to 3000.

K-factor (FIDE)

FIDE only. The UKD k-factor follows your rating.

Games
# Opponent’s rating Your score
1
2
3
4
5
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7
8
9
10
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13
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18
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20

Up to 20 games; leave the rows you do not need empty. UKD: leave the rating empty for an opponent without a UKD.

Free, without an account. Nothing you enter is stored.

How the FIDE rating change is calculated

  1. Rating difference. For each game take the opponent’s rating minus yours. Below 2650, a difference of more than 400 points counts as 400.
  2. Expected score. FIDE’s conversion table turns the difference into an expected score: 0.50 for equal ratings, 0.64 for the player 100 points higher, 0.36 for the one 100 points lower.
  3. Per game. ΔR = your score (1, ½ or 0) minus the expected score.
  4. The change. K × the sum of ΔR, rounded to a whole number (a half away from zero).

K-factor: 40 until you have 30 rated games, and for players under 18 rated below 2300; 20 while your rating is under 2400; 10 once you have reached 2400. If K times the number of games in the tournament would pass 700, K becomes the largest whole number that keeps it within 700: with K 40 and 20 games, K is 35.

Example. A player rated 1800 with K 20 beats a 1900 (expected 0.36, ΔR +0.64) and draws with a 1750 (expected 0.57, ΔR −0.07). The change is 20 × 0.57 = 11.4, rounded to +11: the new rating is 1811.

How the UKD change is calculated

The Turkish Chess Federation calculates the national rating (UKD) by its procedure TK-PRS-05, for a player who already has a UKD:

  1. 350-point rule. An opponent rated more than 350 points away from you counts as exactly 350 away.
  2. Expected score. Take the average of those opponent ratings; the difference D from your rating gives your expected score per game (PD) from the federation’s table, and We = PD × the number of games.
  3. The change. ΔD = k × (W − We), W being your points.

k by your UKD: 30 up to 1299, 25 from 1300 to 1599, 20 from 1600 to 1999, 15 from 2000 to 2399, 10 from 2400. A game against a player without a UKD gives k × 0.1 for a win, k × −0.1 for a loss and nothing for a draw. Games not played over the board are not used, and a UKD never goes below 1000. Standard, rapid and blitz are calculated separately, the same way.

Example. A player rated 1500 (k 25) beats a 2000. The opponent counts as 1850, D is 350, the expected score is 0.11, and the change is 25 × (1 − 0.11) = +22.25: about 1522.

The procedure does not say how D and ΔD are rounded. The calculator rounds D to a whole number before the table lookup, shows ΔD to two decimals and rounds the new rating to a whole number, so its result is an estimate: the federation’s published list is the official figure. A player without a UKD gets a first rating from performance ratings after at least 5 games; this calculator does not cover that.

Club ratings on ChessLivo

Clubs on ChessLivo get their own ratings: each finalized club tournament updates its players’ ratings with the FIDE formula above, separately for standard, rapid and blitz. They stay your club’s ratings: tournaments on ChessLivo are not FIDE-rated or UKD-rated.

More in the help guides.

Rating calculation questions

How is a FIDE rating change calculated?
For each game, your score minus the expected score from FIDE’s table gives ΔR; the change is K times the sum of ΔR, rounded to a whole number. Below 2650 a rating difference of more than 400 points counts as 400.
Which K-factor do I have?
40 until you have played 30 rated games, and for players under 18 rated below 2300; 20 while your rating is under 2400; 10 once you have reached 2400. K times the number of games in a tournament may not pass 700.
How is the UKD calculated?
By the Turkish Chess Federation’s procedure: opponents count at most 350 points away from you, their average gives your expected score per game from the federation’s table, and the change is k × (points − expected points), with k from 30 down to 10 by your rating.
Is the result official?
No. It is an estimate by the published rules. FIDE’s rating list and the Turkish Chess Federation’s UKD list are the official figures, and they may count games or round differently.
What if I play an opponent without a rating?
For the UKD, leave the opponent’s rating empty: a win gives k × 0.1, a loss k × −0.1 and a draw nothing. For a FIDE calculation, enter only games against rated opponents.

Ratings for your club’s tournaments

Run your club’s tournaments on ChessLivo: once a tournament is finalized, every player’s club rating is updated with the FIDE formula.

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