About
Engage in real-time Sudoku battles against friends or other players. Race to solve identical grids, claim squares first, and strategize with bonus cells and streak multipliers. Compete in leagues, wager in-game currency, and customize your experience.
What's New in Kosudoku
1.7
September 22, 2026
Every puzzle is now guaranteed solvable by reasoning alone. Previously a small number of Hard and Expert boards could only be finished by guessing — those are gone, on all four difficulties. Also fixes a problem where picking a username could quietly fail, which in rare cases left a player harder for friends to find. If the name you want is taken you'll now be told straight away.
MoreSubscriptions & In-App Purchases
$0.99
10 Quickets
Adds 10 Quickets to your balance.
FAQ
How does Kosudoku multiplayer work?
In Kosudoku, you and your opponent share the exact same Sudoku grid and solve it simultaneously. Your opponent's moves appear on your screen in real-time, color-coded by player. The first person to solve a square claims it.
Does Kosudoku have ads?
No, Kosudoku is completely ad-free. The developers state it has never shown an advertisement and never will, ensuring an uninterrupted gaming experience.
Can I play Kosudoku offline?
While the core multiplayer experience requires an internet connection, Kosudoku offers a solo play mode. This allows you to practice and chase your best times and scores offline.
What are Quickets in Kosudoku?
Quickets are the in-game currency earned through wins, streaks, and daily rewards. They can be spent in the store on cosmetic items like board skins, themes, fonts, and player colors.
How do the leagues in Kosudoku function?
Kosudoku features weekly league groups of up to 20 players. Finishing in the top three promotes you to a higher rank, while lower placements can lead to demotion. Ranks range from Bronze to Grandmaster.
Is Kosudoku available on different devices?
Yes, Kosudoku is fully cross-platform. You can challenge friends and compete in the same live matches, leagues, and leaderboards regardless of the device they are using.
What is the age rating for Kosudoku?
Kosudoku has an age rating of 12+. This indicates it is suitable for players aged 12 and older.
How often is Kosudoku updated?
The latest version of Kosudoku is 1.5, and it was last updated on September 8, 2026. This suggests a relatively active development cycle.