🧠 Free 16×16 Sudoku Online

A 16×16 Sudoku uses numbers 1–16 and sixteen 4×4 boxes. Only for seasoned puzzle solvers. No login required — play instantly.

▶ Play 16×16 now — free

Choose your difficulty

Select a difficulty level to start playing. All puzzles are free, generated instantly, and have a unique solution.

😊
Easy
55% filled
😤
Hard
30% filled

About 16×16 Sudoku

A 16×16 Sudoku uses numbers 1–16 and sixteen 4×4 boxes. Only for seasoned puzzle solvers. All puzzles on SudokuMaster.org are algorithmically generated with a guaranteed unique solution. No registration, no downloads — just click and play.

Tip: New to Sudoku? Start with Easy difficulty and use the Notes feature to track candidate numbers as you narrow down each cell.

Other grid sizes

4×4
Mini grid for beginners
6×6
Step up from 4×4
9×9
The classic Sudoku
12×12
Extended challenge

Frequently asked questions

What are the rules for 16×16 Sudoku?

Fill every row, column and box with numbers 1 to 16 so each number appears exactly once. Same rules as classic Sudoku — just a different grid size.

Is there a time limit?

No. There is no time limit. The timer shows how long you have been playing, but you can take as long as you need.

Can I save my progress?

Yes. Your puzzle is automatically saved every 15 seconds. If you close the tab and come back, your progress will be restored.

Ready to play?

Free 16×16 Sudoku — no login, no download, works on all devices.

▶ Play 16×16 Sudoku now