Killer Sudoku 1v1
Who adds it up first?
Same cages, same sums, same givens. Send a friend a link, start on the same 3-2-1, and fill all 81 squares before they do.
Free, no account. Send the link, keep this page open, and the race starts the moment your friend opens it.
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Killer Sudoku 1v1
Sudoku rules, and every dashed cage adds up to its sum. A wrong digit adds 5 seconds.
How a Killer Sudoku duel works
- 1One grid for both
A fresh Killer Sudoku is made for your match, with exactly one solution. You and your friend get the same cages, sums and givens.
- 23-2-1, go
The race starts the moment your friend opens the link: a shared countdown, so you both start solving at exactly the same time.
- 3Rows, columns, boxes, cages
Each row, column and box holds 1 to 9 once, and each cage adds up to its sum with no repeats. Their bar counts the squares they have filled correctly.
- 4Wrong digit = +5s
A wrong digit is flagged straight away and adds five seconds. Notes are free; hints are off.
Who wins?
Lowest time wins: from the shared start to your last digit, plus five seconds per wrong digit.
The other player wins straight away.
Either of you can offer a rematch: one tap, a new grid, a new 3-2-1.
Beat a friend at Killer Sudoku
Same cages, same sums. Fill the grid before your friend does.
Alex challenged you to Killer Sudoku ⚡ Same puzzle, one shot. Can you beat me?
dailyfungames.com/killer-sudoku/1v1/?c=k3x9p2mz Stay on this page: the race starts the moment they open it.
- Send a link
WhatsApp, text, anywhere. No sign-up needed.
- Same puzzle
You both get the exact same board.
- Race & rematch
See who won, then go again.
How to beat your friend at Killer Sudoku
Two-square cages of 3, 4, 16 or 17 have only one possible pair. Note them straight away.
Every row, column and box adds up to 45. A box covered by cages except for one square gives that square away.
Select a square and the line above the number pad lists every set of digits that still fits its cage.
Pencil marks cost nothing. Wrong digits cost five seconds. When unsure, note it.
Why Killer Sudoku is made for 1v1
Killer Sudoku adds arithmetic to the classic: cages whose digits must add up to a sum, with no repeats. With almost nothing given, the race is about who spots the forced cages first, and seeing your friend’s bar jump when they crack a box is the push you need.
Every Killer Sudoku 1v1 gets its own freshly generated grid with exactly one solution, and both players get the identical cages and sums. The finished board is checked on our server, and the time is measured there from the shared start, plus five seconds for every wrong digit.
Races are live. Send the link, keep the page open, and the moment your friend opens it you both get the same 3-2-1. If someone leaves mid-race or stops playing, the other player wins, and either of you can call a rematch in one tap. It is free, it runs in any browser, and nobody needs an account: just a name.
Prefer to play alone? Today’s daily Killer Sudoku is the same for everyone, with its own leaderboard and streak.
Killer Sudoku 1v1 questions
Can I play Killer Sudoku against a friend online?
Yes. Tap “Challenge a friend”, send the link by WhatsApp, text or any app, and your friend gets the exact same grid. Keep the page open: the race starts the moment they open it.
How is the winner decided in Killer Sudoku 1v1?
The lowest time wins: from the shared start to your last digit, plus five seconds for every wrong digit. Times are measured on our server.
How hard is the race grid?
Races use an easy grid, with smaller cages and a few digits given, so a match takes minutes rather than half an hour.
Does a 1v1 match use the daily Killer Sudoku?
No. Matches use their own fresh grids, so racing never spoils today’s daily or touches your daily streak.
Is Killer Sudoku 1v1 free?
Yes, completely free in your browser on phone or computer. No download and no account: your friend just opens the link, picks a name, and plays.