Extreme Sudoku Support

On-device Sudoku generation, solving, validation, saving, and export with a formally verified solver core.

Support

For help, questions, or bug reports, contact:

When reporting an issue, please include the app version, device model, iOS or iPadOS version, board dimensions, box layout, and seed if applicable.

Local generation and device limits

Extreme Sudoku performs puzzle generation and solving locally on your iPhone or iPad. No puzzle-generation server is used.

The app supports compact beginner boards such as 4×4, 6×6, and 8×8, classic 9×9 Sudoku, larger boards such as 16×16 and 25×25, and generalized rectangular layouts. Experimental boards have been tested through 36×36 on an iPhone 15 Pro.

Very large configurations may require substantial processing time and memory. Practical limits depend on the device, available per-app memory, sustained processor load, and thermal conditions. iOS or iPadOS may terminate an extremely demanding run when system resource limits are reached.

Formal verification note

Extreme Sudoku uses an exact-cover solver core formally proven using the Rocq Prover. When the solver returns a solution, that solution satisfies the encoded exact-cover constraints.

Privacy

The app requires no account, sign-in, advertising, tracking, or network connection for its primary functionality.

Read the Privacy Policy