The cages are always clear
On paper, dotted lines and sums quickly blur together. Online, the cages are drawn sharply and every sum label sits in its place — in a large, readable font.
Play killer sudoku online
Playing killer sudoku online is puzzling without the fuss: no booklet, no scrap paper for the sums, no eraser. You open BreinPlezier in your browser and the cages are already neatly drawn, with the sum label in the corner — on your computer, tablet, or phone, at your own pace.
Why killer sudoku online works so well
Error checking that includes the cages
One button checks not just rows, columns, and boxes, but also whether your cages are correct: duplicate digits and wrong sums are highlighted for you.
Your board is saved automatically
Taking a break or continuing tomorrow? Your puzzle will be exactly as you left it — saved automatically on your own device, separate from your regular sudoku.
Four levels, always a fresh grid
From Easy with starting digits to Expert with an almost empty board. Every puzzle is new and is guaranteed to have exactly one solution.
This is how I want to play
At my own level
Choose Easy, Medium, Hard, or Expert and play as many killers as you like, with hints and error checking within reach.
Play killer sudokuOne killer every day
The daily killer is the same for everyone. Build your own streak, separate from your regular sudoku streak.
Daily Killer SudokuWant reassurance it's free?
Read why killer sudoku on BreinPlezier is completely free — no account and no hidden costs.
About free killer sudokuNew to this variant? With the killer sudoku rules in plain language you'll know how the cages work within five minutes.
Frequently asked questions about killer sudoku online
What do I need to play killer sudoku online?
Just a device with a web browser: a computer, laptop, tablet, or phone. You don't need to install anything or create an account.
Are the cages easy to see on a small screen?
Yes. The grid is made extra large and the sum labels stay readable, even on a phone. On a tablet or computer you have even more room.
Is my puzzle saved when I stop?
Yes, automatically and on your own device. When you come back later, your board will be exactly as you left it — including the cages and the digits you filled in.
Can I also play with the keyboard?
Yes. You move through the grid with the arrow keys and type digits with the keyboard — handy on a computer or laptop.