Free tool
Chess Performance Rating and Norm Calculator
US Chess titles are rating titles, not FIDE-style norms. This page turns a score into a performance, compares it with class thresholds, and tracks the 300 games above 2200 that create the Original Life Master floor.
A 100 percent score is 400 points above the highest opponent, and a zero score is 400 below the lowest. That is the note on the official estimator. Other scores use the FIDE rating-difference table added to the average opponent.
For the rating change itself, use the round-by-round estimator.