RESTLESS MONKEYA LITTLE PLAY. A LITTLE POSSIBILITY.
THE NEXT NUMBER IS A LITTLE DISCOVERY

A quiet little challenge. A satisfying little click.

YOUR LITTLE BRAIN BREAK

Beginner

Classic 9 × 9
0 / 81 filled
0 mistakes00:00

Tap a square, then choose a number. You’ve got this.

Progress saves on this deviceKeyboard: 1–9 · N notes · H hint · arrows to move
01

One of each.Every row needs 1 through 9.

02

Up and down, too.Every column follows the same rule.

03

Think inside the box.Each 3 × 3 box needs all nine.

About Happy Sudoku ＋
Restless Monkey Software

Built by Restless Monkey Software. Curious code. Practical tools. And a little time to play.

Original game implementation. Rules and feature research: Wikipedia and Sudoku.com. Puzzles have one solution; levels reflect the solving techniques needed. Hard puzzles may require techniques beyond the built-in coach.

Your puzzle, settings and statistics stay in this browser. They do not sync between devices or between the temporary game address and sudoku.jdheil.com. Shared links contain the starting puzzle, not your answers.