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Single-match Elo-style illustration

Calculate one result under the displayed logistic formula with a scale of 400 and your chosen K. This does not create tournament pairings or official ratings.

Use this result well

Inputs that matter
Player rating, Opponent rating, Chosen K factor, Match result
Output to expect
Illustrative updated rating
  • Check the units and required inputs before comparing results.
  • Keep the assumptions with a copied result so you can reproduce the calculation later.
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Reference & details

How it works

Entered quantities and terms

Calculate one result under the displayed logistic formula with a scale of 400 and your chosen K. This does not create tournament pairings or official ratings.

Calculation

Expected score E = 1 ÷ (1 + 10^((opponent − player)/400)); updated rating = player + K × (score − E)

Scope and limits

Expected score is not necessarily win probability when draws are possible. No rating floor, rating-difference cap, official rounding or batch update rules are applied. No Swiss draw, seeding list or multiplayer rating is generated.

Updated: September 2026

Example Scenarios

Illustrative inputs only; replace them with your own quantities, quotes or terms.

Player rating: 1500Opponent rating: 1500Chosen K factor: 32Match result: win

1,516

FAQ

No. Rating systems differ. This calculates only the displayed single-match formula.

No. Pairings, rematches, byes and standings must follow the event rules and pairing system.

About Single-match Elo-style illustration

Calculate one result under the displayed logistic formula with a scale of 400 and your chosen K. This does not create tournament pairings or official ratings. Mathematical illustration with a fixed logistic scale of 400.