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Interactive Tool

Elo Rating Calculator

Enter two ratings to see each side's win probability and exactly how many points they gain or lose. Adjust the K-factor and other settings to simulate any match, 1v1 or free-for-all.

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Match Setup

Controls rating change volatility

Affects expected outcome probability

Reduces rating losses by this %

Match Preview

Player
1200
VS
Even Match
Opponent
1200
50% win 50% win
Selected Outcome
Player Wins

Adjust settings and calculate to see rating changes

Rating formula

Δ = 32 × ( S − 1 1 +10d′/400 )

d′ = d, limited to ±400

Largest change from one match: +29.1 / −29.1

32 K-Factor 10 Curve Factor 400 Influence Range 400 Cap Range d rating diff S result (1 win, 0 loss)

Rating change vs opponent rating difference (updates live as you edit settings, includes capping)

+290-29-6000+600opponent rating diffWinLoss

The same engine runs every Team Up Discord leaderboard, with these settings per board.

01 The basics

How It Works

Expected Outcome

The system calculates the probability of each player winning based on their rating difference. Higher-rated players are expected to win more often.

Rating Adjustment

Upsets (underdog wins) cause larger rating swings. Expected outcomes cause smaller changes. The K-factor controls the overall magnitude.

Quick Guide

  • 1 Enter Player and Opponent Ratings, or switch to FFA mode to add multiple players
  • 2 Select the Match Result (1v1) or assign Placements (FFA)
  • 3 Click Calculate to see the rating changes for all players
  • 4 Expand Core Elo Settings to adjust K-factor, influence range, and more
02 Watch & learn

Learn How Elo Works

Watch these videos for an in-depth look at the math and theory behind the Elo rating system. Prefer to read? What Elo means in gaming covers the basics, from the formula to "elo hell".

03 Tuning dials

Key Parameters

K-Factor

Default: 32

Controls rating volatility. Higher values mean bigger rating swings per match.

16–24: Stable (experienced players)32: Standard40+: Volatile (new players)

Influence Range

Default: 400

The rating difference at which win probability shifts significantly. A 400-point difference gives the favorite ~91% expected win rate.

Loss Dampen

Default: 0%

Reduces rating losses by a percentage. Useful if you want to soften the impact of losses while keeping win rewards the same.

FFA Distribution

Default: On

In Free-for-All matches, each player is compared against every opponent pairwise. When enabled, the total rating change is divided by the number of opponents, keeping FFA rating changes on the same scale as 1v1 matches.

Rating Capping

Default: On (±400)

Limits extreme rating changes when skill gaps are large. Prevents favorites from gaining almost nothing for expected wins or underdogs from losing almost nothing for expected losses.

04 See it in action

Example Scenarios

Even

Even Match

Two players with equal ratings (1200 vs 1200)

Winner gains: +16
Loser loses: −16
Expected

Expected Win

Favorite wins (1400 beats 1200, 76% expected)

Favorite gains: +8
Underdog loses: −8
Upset

Upset

Underdog wins (1200 beats 1400, 24% expected)

Underdog gains: +24
Favorite loses: −24

Values shown use default settings (K-factor: 32, Influence Range: 400), rounded as the bot records them

05 Reference

Elo Win Probability by Rating Difference

How likely the higher-rated side is to win, and how many points each side gains for winning.

Rating differenceFavorite winsUnderdog winsFavorite gainsUnderdog gains
050%50%+16+16
5057.1%42.9%+14+18
10064%36%+12+20
15070.3%29.7%+9+23
20076%24%+8+24
25080.8%19.2%+6+26
30084.9%15.1%+5+27
40090.9%9.1%+3+29
50094.7%5.3%+2+30
60096.9%3.1%+1+31
80099%1%0+32

K-factor 32, influence range 400, no rating cap, rounded to whole points. Win chances count a draw as half a win.

06 Questions

Elo Calculator FAQ

How does the Elo calculator work out win probability?

Each side's expected score is 1 / (1 + 10^(rating difference / 400)), where the difference is the opponent's rating minus yours. Two equal ratings give 50% each; a 200-point favorite is expected to win 76% of the time. Draws count as half a win in this figure, so read it as an expected score rather than a strict win rate.

What is the win probability for a 400-point Elo difference?

About 90.9% for the higher-rated player and 9.1% for the lower-rated one. 400 points is the scale of the formula: every 400 points of gap multiplies the favorite's odds by ten. A 100-point gap is 64%, 200 is 76%, and 800 is 99%.

How many Elo points do you gain or lose per match?

The change is K × (actual score − expected score). With K = 32, an even match moves both players 16 points. A 200-point favorite who wins gains only 8, because the win was expected; if the underdog wins instead, they gain 24. The two players' changes always add up to zero in a 1v1.

What K-factor should I use?

K sets how far one result moves a rating. 32 is the common default and suits most gaming communities. Use 16–24 for an established ladder where ratings should be stable, and 40 or more for new players whose rating is still finding its level. Chess federations use a similar idea, starting new players on a higher K and lowering it as they play more games.

Can I use this Elo calculator for football, chess or esports?

Yes — the core formula is the same everywhere. Football Elo systems such as the World Football Elo Ratings add a goal-difference multiplier and home advantage on top, which this calculator does not model; raise K for more important matches to approximate it. For chess and esports, the standard settings here are a close match.

How are draws calculated?

A draw scores 0.5 for each side. Between equal ratings it changes nothing. Between unequal ratings the favorite loses points and the underdog gains them: a 200-point favorite who draws moves −8.

Put these ratings to work

This calculator runs the exact same Elo engine as the Team Up bot. Add it to your Discord server and every setting above is yours to tune per leaderboard.