Chess Meadow

Chess match, rating & Chess960 tools

Rp = Ra + dp · FIDE Handbook B.01 and B.02

Chess performance rating calculator

Your performance rating is the average rating of your opponents plus a rating difference read from FIDE’s table for your score. Enter each opponent’s rating and your result.

Games

Result

Performance rating (FIDE)

2365

Rp = Ra + dp = 2322 + 43

Average opponent (Ra)
2322
Score
5 of 9 (55.6%)
Won, drawn, lost
3 · 4 · 2
dp from table 8.1.1
+43
  • p = 5 ÷ 9 = 55.6%, read from the table as .56, which gives dp +43.
  • Estimate by the “algorithm of 400” (not FIDE’s method): (sum of ratings + 400 × (wins − losses)) ÷ games = 2367.

Expected score for any rating difference

2212 v 2318Difference 106Expected score .36 for 2212, .64 for 2318Over 10 games: 3.6 to 6.4.

How FIDE calculates a performance rating

FIDE’s performance rating is Rp = Ra + dp. Ra is the average rating of your opponents, rounded to the nearest whole number with 0.5 rounded up. Your fractional score p is your points divided by the number of games, and table 8.1.1 converts it into the rating difference dp: 5 points from 9 games is 55.6%, read as .56, which gives +43. With the example above, an average of 2322 plus 43 makes 2365.

The second tool reads table 8.1.2: the expected score for each player for any rating difference, the figure the rating calculator uses for every game.

FIDE table 8.1.1: fractional score p to rating difference dp
pdppdppdppdppdppdp
1.0+800.83+273.66+117.49−7.32−133.15−296
.99+677.82+262.65+110.48−14.31−141.14−309
.98+589.81+251.64+102.47−21.30−149.13−322
.97+538.80+240.63+95.46−29.29−158.12−336
.96+501.79+230.62+87.45−36.28−166.11−351
.95+470.78+220.61+80.44−43.27−175.10−366
.94+444.77+211.60+72.43−50.26−184.09−383
.93+422.76+202.59+65.42−57.25−193.08−401
.92+401.75+193.58+57.41−65.24−202.07−422
.91+383.74+184.57+50.40−72.23−211.06−444
.90+366.73+175.56+43.39−80.22−220.05−470
.89+351.72+166.55+36.38−87.21−230.04−501
.88+336.71+158.54+29.37−95.20−240.03−538
.87+322.70+149.53+21.36−102.19−251.02−589
.86+309.69+141.52+14.35−110.18−262.01−677
.85+296.68+133.51+7.34−117.17−273.00−800
.84+284.67+125.500.33−125.16−284
FIDE table 8.1.2: rating difference D to expected score PD for the higher (H) and lower (L) rated player
DHLDHLDHLDHL
0–3.50.5092–98.63.37198–206.76.24345–357.89.11
4–10.51.4999–106.64.36207–215.77.23358–374.90.10
11–17.52.48107–113.65.35216–225.78.22375–391.91.09
18–25.53.47114–121.66.34226–235.79.21392–411.92.08
26–32.54.46122–129.67.33236–245.80.20412–432.93.07
33–39.55.45130–137.68.32246–256.81.19433–456.94.06
40–46.56.44138–145.69.31257–267.82.18457–484.95.05
47–53.57.43146–153.70.30268–278.83.17485–517.96.04
54–61.58.42154–162.71.29279–290.84.16518–559.97.03
62–68.59.41163–170.72.28291–302.85.15560–619.98.02
69–76.60.40171–179.73.27303–315.86.14620–735.99.01
77–83.61.39180–188.74.26316–328.87.13> 7351.0.00
84–91.62.38189–197.75.25329–344.88.12

Sources

Questions

How do I calculate my chess performance rating?

Average your opponents’ ratings, work out your score as a fraction of the games, and add the rating difference FIDE’s table gives for that fraction. 50% adds nothing; 75% adds 193.

What performance do I need for a GM norm?

At least 2600 (2599.5 before rounding) against opponents averaging at least 2380, with at least 35%, plus the other norm rules in the FIDE Title Regulations.

What is my expected score against a stronger player?

Read it from table 8.1.2: 100 points below an opponent you are expected to score .36 a game, 200 points below .24, and 400 points below .08.