ELO Rating Calculator — Rating Change After a Match
Enter your current rating, your opponent's rating, the match outcome, and the K-factor to see your new ELO rating and how many points you gained or lost.
Match result
+20.5 points gained
- 1
Rating difference (opponent − you)
1,600 − 1,500 = 100 - 2
Expected score
1 ÷ (1 + 10^(100 ÷ 400)) = 0.3599Probability of winning predicted from the rating gap. - 3
Actual score
Win → 1 = 1 - 4
Rating change (K × (actual − expected))
32 × (1 − 0.3599) = 20.5 - 5
New rating
1,500 + (20.5) = 1,520
How does this calculator work?
ELO rating change = K × (actual score − expected score), where expected score = 1/(1 + 10^((opponent − you)/400)). Win gives actual score 1, draw 0.5, loss 0. The K-factor (commonly 16–32) sets how many points a single result can move your rating. Your new rating = old rating + change.
Formula
How this is calculated
The ELO system, devised by physicist Arpad Elo for chess and now used across sports and competitive games, adjusts ratings based on the difference between actual and expected performance. The expected score E is the probability of winning (or half for a draw) predicted from the rating gap: a 200-point gap gives roughly 75 % win probability to the higher-rated player.
After the match, the rating change is K × (actual score − expected score), where the actual score is 1 for a win, 0.5 for a draw, and 0 for a loss. The K-factor controls how much a single result shifts the rating: FIDE uses K = 40 for new players (under 30 rated games), K = 20 for players under 2400, and K = 10 for those who have ever exceeded 2400. Many online platforms and sports leagues use K = 32. A higher K makes ratings more reactive to individual results.
Winning against a stronger opponent yields more points than beating a weaker one; losing to a weaker opponent costs more than losing to a stronger one. Over time, ratings converge to a player's true skill level. This calculator works equally for chess, tennis, table tennis, esports, or any head-to-head competition that uses the ELO algorithm.
Frequently asked questions
FIDE (chess) uses K = 40 for new players, K = 20 for players rated below 2400, and K = 10 for those who have ever reached 2400. Many online platforms and sports organisations use K = 32. A higher K means larger swings per match — suitable for newer players whose true rating is uncertain, while a lower K stabilises experienced players' ratings.
The expected score is the probability of winning the match predicted by the ELO model based purely on the rating gap. A score of 0.75 means the model gives you a 75 % chance of winning. If you win (actual score 1) against an expected score of 0.75, you gain K × 0.25 points — less than if you had upset a much higher-rated player.
Yes. ELO or ELO-derived algorithms are used in FIDE chess, USCF chess, FIFA women's football ranking, table tennis (ITTF), esports platforms such as Riot Games and Valve, sports analytics, and many competitive apps. Variants like Glicko-2 and TrueSkill add uncertainty measures but share the same core expected-score concept.
Also known as
TG we-Calculate Editorial Team. (2026). ELO Rating Calculator — Rating Change After a Match [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/elo-calculator
TG we-Calculate Editorial Team. "ELO Rating Calculator — Rating Change After a Match." TG we-Calculate. 2026. https://we-calculate.com/calculator/elo-calculator.
TG we-Calculate Editorial Team, "ELO Rating Calculator — Rating Change After a Match," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/elo-calculator
@misc{wecalculate_elo_calculator, title = {ELO Rating Calculator — Rating Change After a Match}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/elo-calculator}}, year = {2026}, note = {TG we-Calculate} }
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