Official Rulebook

KenKen is a numerical logic puzzle played on an NxN grid, where N is between 3 and 9. Each row and each column must contain every digit from 1 to N exactly once. Every sanctioned puzzle has a single, machine-verified solution.

Cages. Outlined groups of cells display a target and an operation. The digits inside must combine, using that operation, to reach the target. Single-cell cages state their digit directly. Digits may repeat within a cage only if they sit in different rows and columns.

Junior. Ages 8 to 14. Grids from 4x4 to 6x6. Addition through division.

Open. All ages. Grids from 5x5 to 8x8. All four operations, standard cages.

Elite. Invitational and qualifier-based. Grids up to 9x9, including NO-OP variants where the operation is hidden.

Rounds. Events run in multiple timed rounds. Each round presents a fixed set of puzzles that all competitors solve simultaneously.

Time Limits. Every puzzle carries a maximum time based on its size and difficulty. Competitors who exceed the limit are scored only on cells filled correctly.

Brackets. Elite events may use single-elimination brackets in the final stages, pairing solvers head to head.

Every puzzle is scored on three factors, in this order of priority.

• Completion: was the puzzle fully solved.
• Accuracy: were all cells correct.
• Speed: how quickly it was finished, used to break ties.

Hybrid Rating. Results feed a rating that weights strength of field, so wins against higher-rated opponents carry more value. Only sanctioned events affect official ratings.

Materials. Pencil and paper only. No electronic devices, calculators, or reference materials. Notes within the grid are permitted.

Fair Play. Any form of assistance, communication, or pre-solved material is prohibited. Competitors agree to the Federation code of conduct on registration.

Verification. A puzzle counts as solved only when every cell is correct and all cage constraints are satisfied. Officials verify all solutions before final scoring.

Disputes. Solving disputes are resolved by the on-site judge, with final appeals heard by the Federation Ethics Chair.

This rulebook is maintained by the KenKen Federation and amended only by a vote of ratified national chapters. For licensing, sanctioning, or press, reach us at hello@kenken.games.