USCF Rating Calculator (US Chess Rating Estimator)

Free USCF rating calculator: estimate your new US Chess rating after a tournament, with K-factor, bonus points, provisional ratings and rating floors.

The interactive uscf rating calculator (us chess rating estimator) loads here. It runs in your browser and is free to use.

Enter your rating, the number of rated games you have played and your results, and the calculator estimates your new US Chess (USCF) Regular rating. It is an estimate: your official rating is computed by US Chess after the tournament director submits the event and it is rated. Floors, unrated opponents and the monthly supplement can make the posted number differ.

How US Chess ratings are calculated

US Chess uses its own version of the Elo system, described in "The US Chess Rating System" by Mark Glickman and Thomas Doan (the current revision is dated April 6, 2026). Your whole tournament is rated at once, using your rating before the event.

Step 1: effective number of games. Your rating counts as if it were based on N′ games: the number of rated games you have played, but never more than N*, a value that grows with your rating (about 17 at 1500, 29 at 2000 and 50 for 2355 and above). A small N′ means your rating moves quickly.

Step 2: special or standard formula. If your rating is based on 8 or fewer games, or every rated game you ever played was a win (or every one a loss), the special formula is used. (The 8-game test uses your actual games, not N′.) It counts your old rating as N′ games scored 50% and finds the rating that makes your score "expected" with a straight-line expectancy capped at 400 points. With all opponents within 400 points, that is the provisional formula (N′ × old rating + opponents' ratings + 400 × (wins − losses)) ÷ (N′ + games). After all wins (losses), the old rating counts 400 points lower (higher). Ties go to the rating closest to your old one, and the cap is 2700.

Otherwise the standard formula applies: new rating = old rating + K × (score − expected score), with K = 800 ÷ (N′ + games in the event). Expected score per game is 1 / (1 + 10^(−difference/400)).

Step 3: bonus points. With 3 or more games, a big overperformance earns a bonus: K × (score − expected) − B × √(games, at least 4), if positive, with B = 10 since January 1, 2025. The bonus is skipped when you played the same opponent more than twice (or twice in a 3-game event).

Worked example

You are rated 1500 with 50 rated games, so N′ = 16.6. In a four-round Swiss you beat 1600, 1550 and 1700 and draw a 1450. Your expected score is 1.60 and you scored 3.5. K = 800 ÷ 20.6 = 38.9, so the regular gain is 38.9 × 1.90 = +73.9. The bonus threshold is 10 × √4 = 20, giving a bonus of 73.9 − 20 = +53.9. Your new rating is about 1628.

Rating floors

A rating floor is the lowest your rating can drop. Section 5 of the US Chess specification sets them:

• Absolute floor: no rating goes below 100. For over-the-board ratings your personal absolute floor is 100 + 4 × wins + 2 × draws + the number of events with at least 3 rated games, up to 150.
• Peak-based floor: once you have an established rating (more than 25 games), take your highest established rating rounded to a whole number, subtract 200 and go down to the next floor from 1200 to 2100. A peak of 1941 gives 1700 and a peak of 1999.51 gives 1800. A peak of 1388 is below the 1200 level, so only the absolute floor applies.
• Highest floor: peak-based floors stop at 2100. Original Life Masters keep 2200, and winning $4,000 or more in an under-2000 section can set a prize floor.

Enter your peak and the calculator stops the estimate at your floor. Floors are kept separately for Regular, Quick and Blitz.

Unrated players and unrated opponents

Your first rating. With no rating to convert, US Chess starts from your age: 50 × age from 2 to 26 (a 12-year-old starts at 600) and 1300 above 26. Without a birth date, an adult starts at 1300 and anyone else at 750; the calculator assumes an adult when you leave the age empty. That starting value carries no game weight (N = 0), so your first rating comes from the special formula on the event alone. Example: an unrated 12-year-old beats a 1000 and a 900, draws a 1100 and loses to a 1200: (4200 + 400 × (2 − 1)) ÷ 4 = 1150.

Unrated opponents are handled in passes. First, each unrated player gets an estimate from the special formula, with their starting value counted as one game and unrated opponents counted at their age-based value. Then everyone gets an intermediate rating, with unrated opponents counted at those estimates. Finally, everyone is rated again against the opponents' intermediate ratings. Add unrated opponents with their age and, if known, their event score.

How to look up your official USCF rating

1. Go to uschess.org and open the player search in the Member Services Area (MSA).
2. Search by last name or by your 8-digit US Chess ID.
3. Your page lists your ratings, history and crosstables.

Many tournaments pair with the monthly rating supplement, so the rating used at your next event can be older than your latest one.

Limits of this estimate

The calculator shows the intermediate rating: US Chess's final pass uses every opponent's updated rating from the event, which a single-player calculator cannot know. Prize and Life Master floors, matches and ratings converted from FIDE are not modelled. Compare with the FIDE rating calculator, which uses different rules.

Sources

The formulas follow "The US Chess Rating System" by Mark E. Glickman and Thomas Doan, revision of April 6, 2026, published by US Chess. We checked the calculator against it, including its worked examples, on November 2, 2026.