CalcFxC Elo Expected Score Formula Calculator

Calculates the expected score of a player with an Elo rating Ra against a player with an Elo rating Rb.

 

 

Formula: 1/(1+10^(-(Ra-Rb)/400))

Ra: Rating of player a.

Rb: Rating of player b.

Example 1

For a player with a rating of 1600, what is their expected score against a player rated 1450?

 

Value	Keystrokes	Display	Description
1600	STO Ra	1,600.0000	Stores the Ra value.
1450	STO Rb	1,450.0000	Stores the Rb value.
	Ea	0.7034	Calculates Ea.

Example 2

Calculate the rating of an opponent where the expected score of player a is 0.6.

These keystrokes assume the values from example 1.

 

Value	Keystrokes	Display	Description
.6	STO Ea	0.6000	Stores the Ea value.
	Rb	1,529.5635	Calculates the Rb value.

Reference:

Elo Rating System- Wikipedia

 

Code for this Calculator.