Sudoku
Fill the board without repeating numbers
How to play
- Fill the empty cells with numbers from 1 to 9.
- Each number can only appear once in each row, column, and 3x3 block.
- Tap a cell, then tap a number on the keypad to fill it in.
- Turn on "Notes" to jot down candidates in a cell without committing.
- Use "Hint" when you get stuck — there's no mandatory timer pushing you.
There's no rush: take your time before filling in each cell.
About this game
Sudoku is a logic game in which you fill a 9x9 grid with the numbers 1 to 9, without repeating any number in the same row, column or 3x3 block. It involves no arithmetic: the numbers work only as symbols.
Sudoku is one of the most studied logic games: to complete the board, you need to rule out possibilities and compare rows, columns and blocks at the same time — a direct exercise in attention and planning, with no luck involved.
On DIVILLI, you choose the level (Easy, Medium or Challenging), can turn on "Notes" to jot down candidates in a cell without committing to them, and use "Hint" whenever you get stuck — with no mandatory timer pushing you along.
You can play on a phone, tablet or computer, right in the browser, with no sign-up and nothing to install. The numbers are large and the number keypad is on the screen itself.
Frequently Asked Questions
Is Sudoku good for the brain?
Sudoku exercises logical reasoning and sustained attention, skills linked to cognitive reserve. It doesn't prevent disease, but it's an enjoyable way to keep your mind active on a regular basis.
Which Sudoku level should I start with?
Easy, already marked as recommended, is the ideal starting point — it has more numbers already filled in. Move up to Medium or Challenging as you gain confidence.
Do I need to be good at math to play Sudoku?
No. Sudoku never asks you to add or multiply. The numbers 1 to 9 are just symbols; what matters is logic: working out which number still fits in each cell.
What should I do when I get stuck in the middle of the board?
Look for the row, column or block with the most numbers already filled in: it has the fewest options left. Another way out is to pick a number, such as 5, and see which cells it can still go in. If nothing works, use Notes or ask for a Hint (up to 3 per game).
What are Notes for?
Notes let you jot down, in a cell, the numbers that are still possible there without committing to any of them. As other cells get filled in, the possibilities shrink until only one is left.
How many numbers are already filled in at each level?
On Easy, 44 numbers; on Medium, 34; on Challenging, 28. The fewer numbers at the start, the more deduction you need to do.
Is there a time limit in Sudoku?
No. There is no countdown and no time limit: take your time before filling in each cell.