Classic and variant sudoku, extreme challenges, photo import & analysis, powerful hints, pro-grade pencil marks and a top-tier solving engine — clean, no ads.
A top-tier solving engine with deep analysis across 70+ techniques — from singles to chains and fish, even the hardest puzzles come apart step by step.
Candidate notes, color marks, chain and region annotations, conflict detection — desktop-grade drafting tools on your phone.
Import puzzles from newspapers, magazines or other apps — printed givens and handwritten digits are told apart, ready to play.
Seven difficulties refreshed daily, same puzzles worldwide, with leaderboards — plus a deep, organized puzzle library.
Powered by a top-tier solving engine, every puzzle can be taken apart step by step — each move comes with a reason you can follow.
Every habit from drafting on paper — plus the things paper can't do.
Pick a digit and watch the candidates light up. Every theme tunes the selected cell, its peers and the candidate highlight; dark themes get their own hint-chain colors too.
Seven levels from Easy to Diabolic, refreshed every day at midnight UTC. You and every player in the world get the very same puzzles.
Puzzles from newspapers, magazines or other apps: scan a photo or screenshot and start playing right away — printed clues and your handwritten digits are told apart correctly.
Every variant has its own puzzles and rule explanations.
Classic play
Explanations
Draft notesVariants
Stats & awards
Dark modeThe choice of serious players — a complete toolkit for sudoku lovers
Sudoku Fun