Mastery

How well you currently handle a skill, from Not started through Learning, Developing and Solid to Mastered.

Last updated October 16, 2026

What it means: Mastery is a score per skill that reflects how you play it now, not over your whole history. It fades when a skill is left alone and ignores luck from a handful of answers.
How it is calculated: Each grade scores Best 1, Correct 0.85, Inaccuracy 0.5, Wrong 0.15 and Blunder 0. A decision's weight halves every 14 days, easy decisions far from the range edge count 0.25 of a normal one, decisions made with the table coach on count 0.5, and 3 imaginary decisions at 50% are added so a few answers cannot look certain. Under 10 decisions or below 60% is Learning, then Developing up to 80%, Solid up to 90%, and Mastered from 90% with at least 30 decisions over 3 separate days and practice in the last 30 days.
Worked example: Today you answer 10 hands in a skill: 8 Best and 2 Wrong. The score is (8 × 1 + 2 × 0.15 + 3 × 0.5) ÷ (10 + 3) = 9.8 ÷ 13, about 75%, which is Developing. The same 10 answers spread over three weeks, with the old ones fading, would move with your recent form instead.
Why it matters: It answers what you have learned and what to work on next. The separate-days rule keeps one cramming session from counting as mastery, which is the same idea behind spaced repetition.