VariantDoku

Variant sudoku, done right.

A curated iOS app for killer, thermo, arrow, and other variant sudokus. Daily puzzles, offline solving, clean rules. No ads, no trackers.

1,880 puzzles
Daily new challenge
Download on the App Store

What's inside

Built for variants

Not a classic sudoku app with extras bolted on — variant rules are first-class from the ground up.

Generated, never scraped

Every puzzle is generated and tested in-house. No third-party content, no licensing surprises.

Daily puzzle

A fresh puzzle every day, ready when you want a focused solve without hunting through a catalog.

Offline solving

Keep solving started and saved puzzles without a connection, including progress, pencil marks, and undo history.

No ads, no trackers

Free tier supported by an optional Variant+ subscription. Your gameplay isn't telemetry.

Made for focus

Pencil marks, error checks, undo, and a UI that gets out of the way while you solve.

Acknowledgements

Puzzle generation, validation, and difficulty research use CP-SAT techniques and Interactive Sudoku Solver (ISS) by sigh as offline analysis tools. ISS is MIT licensed.

Shout-out to Logic Masters Germany, Sven from SudokuPad, and Cracking the Cryptic for their influence on the variant sudoku community.