Kosudoku app icon

Kosudoku

One Sudoku grid. You and a friend. Both solving it at the same time.

Their guesses appear on your screen the moment they make them. Every square belongs to whoever solves it first.

Download for iPhone Download for Android

No ads, ever. Free to play, with optional in-app purchases.

▶ Tap for sound

Two players, one board, nothing staged — that's a real match.

Two players racing on one shared Sudoku board
One board, both of you, live
Streak multiplier building during a game
Streaks and bonus cells
Weekly league standings
Weekly leagues
Home screen showing active and solo games
Your games at a glance
Cosmetics store with board skins and colours
Spend your Quickets
Player profile with stats and rank
Stats and rank

NO ADS. Not a banner, not a video, not one that appears "just this once" between games. Kosudoku has never shown an advertisement and never will.

Kosudoku is Sudoku as a live race. You and your opponent get the identical board and fill it simultaneously — their guesses appear on your screen the moment they make them. Every square belongs to whoever solves it first. Hesitate on a cell you'd worked out, and you'll watch it turn their colour.

That's the whole game: a shared grid, a running scoreboard, and the pressure of knowing someone else is looking at the same empty square you are. Add a friend, build a head-to-head record, and settle it again tomorrow.

Race head-to-head

Build a streak, hunt the bonus cells

Play solo any time

Climb the leagues

Put something on it

Play with friends

Cross-platform. iPhone and Android players compete together in the same live matches, leagues and leaderboards. Challenge any friend, whatever they play on.
No ads, ever. Kosudoku is completely ad-free. No banners, no interstitials, no rewarded videos, no "watch an ad to continue". Your board is never interrupted.
Download for iPhone Download for Android