Calibration
Familiarity is not mastery. This tracks how well your confidence matches your real performance — the single best antidote to the illusion that you know something because it looks familiar.
Sign in to record your predictions and build a calibration history.
How it works
Before you see an answer, you predict how likely you are to be right (25 / 50 / 75 / 95%). We score that prediction against what actually happens. Over many predictions, a pattern emerges: if you say “95% sure” but are right only 70% of the time, you're overconfident — and now you know exactly where. The research is blunt about why this matters: the feeling of knowing (fluency) is a poor guide to actual knowing, and the act of predicting-then-checking is itself what recalibrates it.