Professional Chess Calculator
Accurate, transparent, and fast chess rating calculations trusted by players worldwide
No registration required • 100% free • All calculations run locally
Complete Chess Calculation Suite
Everything you need for chess ratings and tournament calculations in one place
Elo Calculator
Calculate expected scores and rating changes with FIDE and USCF K-factors
Performance Rating
Calculate your TPR and check title norm requirements
Tiebreak Systems
Calculate Buchholz, Sonneborn-Berger, and other tiebreak scores
Time Control
Calculate game duration with increment and delay systems
Rating Converter
Convert between FIDE, USCF, ECF, and online ratings
Expected Score
Calculate win probability based on rating difference
How It Works
Simple, fast, and transparent calculations in three easy steps
Input Your Data
Enter ratings, scores, or tournament results into our intuitive forms
See Calculations
Watch as we show every step and formula used in the calculation
Export Results
Copy, download CSV, or share your results with others
Why Players Trust Us
100% Accurate
Following official FIDE and USCF formulas to the letter
Private & Secure
All calculations run locally - your data never leaves your browser
Lightning Fast
Instant calculations with no server delays or loading times
Educational
Learn how ratings work with transparent step-by-step calculations
Ready to Calculate Your Chess Ratings?
Join thousands of chess players using our professional tools every day
What Players Say
"The transparency is amazing. I can finally understand exactly how my rating changes are calculated."
"Essential tool for tournament directors. The tiebreak calculations save me hours of work."
"Perfect for checking if I'm on track for my IM norm. The TPR calculator is spot on!"