The science
Adaptive difficulty

Hard enough to matter, never hard enough to quit

A session that's too easy is boring; one that's too hard is discouraging. CogDojo keeps you in the narrow band between them by giving every skill a rating and matching the difficulty to it — every session, automatically.

Every skill has an Elo rating

Elo is the rating system chess and competitive games use to measure skill and create fair matchups. CogDojo borrows it: each of your six cognitive skills carries its own Elo. New ratings start at 1200 and live within a 500–2500 range.

After each session, your rating updates based on how you actually did versus how someone at your current rating was expected to do. Beat the expectation and it rises; fall short and it eases back. The size of the move is capped, so one great — or one rough — session nudges your rating rather than throwing it. Over time it converges on your true level for that skill.

From rating to five difficulty bands

Your current rating maps to one of five difficulty levels. That level sets how a game is generated for you — grid size, pacing, the number of distractors, and which rule variants are in play. The bands:

1Level 1

Foundations

Rating Below 900

Gentle introductions. Smaller grids, slower pacing, more time. Where most skills begin.

2Level 2

Building

Rating 900–1300

The patterns get a little denser and the clock a little tighter as the basics settle in.

3Level 3

Steady

Rating 1300–1700

A real workout. This is where many players spend most of their time once they've warmed up.

4Level 4

Sharp

Rating 1700–2100

Demanding pacing and added rules. Reserved for skills you've genuinely built up.

5Level 5

Peak

Rating 2100 and up

The hardest variants we offer. Maximum density, minimum slack. Earned, never handed out.

It reads the room, too

The band isn't set by your rating alone. CogDojo also looks at your recent trend — a run of strong sessions can nudge the next one up a notch before your rating fully catches up, and a string of rough ones can ease it back. The goal is always the same: keep you in the stretch zone, where the challenge is real but the next round still feels worth starting.

Adaptive difficulty is about engagement and fair measurement — keeping practice enjoyable and your ratings meaningful. It's a way to make training stick, not a treatment, and reaching a higher band is an achievement within CogDojo rather than a claim about your everyday abilities.