Sudoku
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About Sudoku

Sudoku started life as "Number Place" in a 1979 American puzzle magazine, was perfected and named in Japan in the 1980s, and by 2005 was in every newspaper on earth. The appeal is purity: no vocabulary, no trivia, no luck — just one rule applied eighty-one times.

Fill the nine-by-nine grid so every row, every column, and every three-by-three box contains the digits one through nine exactly once. Here you get three difficulties whenever you want them, plus a daily puzzle that's identical for every player — same grid, same challenge, compare away. Pencil marks and a mistake indicator round it out.

How to play

Strategy

Tip: Scan for the digit that is already placed in most boxes — it is usually the easiest one to finish locking in across the grid.

Sudoku FAQ

Is the daily sudoku the same for everyone?

Yes — one shared grid per day, so you and a friend can compare times on the identical puzzle. The easy, medium, and hard boards are separate and fresh whenever you want one.

What are pencil marks for?

Noting the candidate digits a cell could still hold. Past the easy level, sudoku is mostly about tracking candidates — pencil marks are how you spot pairs and forced placements.

What's the difference between the difficulties?

Harder boards start with fewer given digits and demand deeper technique — easy solves with basic scanning, hard expects real pencil-mark logic.

Can I play on my phone?

Yes. Tap a cell, then tap a number on the on-screen pad. The same board works with a keyboard on desktop.

Enjoying Sudoku? Try Sweep or Five next, or browse all games.