Play Sudoku online: every puzzle has a unique solution, with Easy, Medium and Hard levels. Pencil notes, hints and undo are all included for when you get stuck. Perfect for a commute break — pure logic, no guessing. No install, no sign-up, any device.
How to play
Pick a difficulty (Easy / Medium / Hard) — every board has a unique solution.
Tap a cell and enter 1–9; switch on pencil notes when unsure.
Fill each row, column and 3×3 box with 1–9 without repeats; use hints if stuck.
Features
Every puzzle is unique-solution — pure logic, no guessing
Easy / Medium / Hard levels
Pencil notes, hints and undo all included
English & Chinese UI, runs locally in your browser
FAQ
Is Sudoku free?
Completely free — no sign-up, no download.
Are the puzzles unique-solution?
Yes — every board can be completed by logic alone.
Can I play on my phone?
Yes — tap to fill, long-press for notes; plays smoothly on any device.