Kodus : Sudoku and Techniques

Kodus is a sudoku puzzle game built around logic, not luck. Every grid ships inside the app and plays offline, with no account and no sign-up. Whether you are learning sudoku for the first time or hunting for truly hard sudoku, the game grows with you.

Six difficulty levels, graded by technique

Easy, medium, hard, expert, master, extreme.

Difficulty is not about how many cells are empty, but about the sudoku techniques a puzzle demands. An "expert" grid needs an X-Wing; a "hard" grid falls to pairs and triples. The level you pick is the work you will actually do — from sudoku for beginners to expert sudoku.

Learn sudoku strategies, step by step

A short tutorial covers the basics, then guided lessons teach eleven sudoku strategies: naked single, hidden single, locked candidates, naked pair, naked triple, hidden pair, X-Wing, Swordfish, XY-Wing, XYZ-Wing, W-Wing. The first two lessons are open to everyone. Training mode then serves a puzzle that demands the technique you pick.

Hints that explain

A hint does not hand you the answer. It points at the area to look at, then names the technique, then colours the notes that survive and the ones that go, right on the grid. You stop at whatever level of detail suits you — a sudoku hint that teaches instead of solving for you.

Daily sudoku

One daily puzzle, the same for everyone, with a calendar tracking the days you cleared and your time on each. A streak builds day after day.

Duel

Face a player at your level on the same grid. Fastest wins. You can watch your opponent's replay, move by move, in their own order. A rating ladder takes you from Bronze to Diamond.

Leaderboards

Level, experience, time per difficulty, days played, daily challenges in a row, duel rating — for classic 9×9 sudoku and Mini 6×6 alike.

Mini 6×6 variant

Small 6×6 grids generated on the fly, in three levels, made for a quick brain game on the go.

Comfort

- Manual or automatic notes (pencil marks)
- Fast entry: pick a digit, then the cells to place it in
- Light, dark and deep black (OLED) themes, or follow the system
- Three font sizes
- Timer off by default, switchable in settings
- Adjustable vibration

Progression

Every puzzle you finish earns experience and levels you up. Levels grant hint, auto-note and life tokens. A profile gathers your statistics, your best times per difficulty, your consecutive-day streak and achievements to unlock.

Saves and Play Games

Your games are stored on your device. Signing in to Google Play Games is optional: it adds cloud saves, leaderboards, achievements and duel mode.

Kodus Premium

You can install and play without paying: six difficulties, the daily challenge, hints, replay, Mini 6×6 and two training lessons are included. A single purchase, with no subscription, unlocks the full technique training, unlimited tokens, the daily calendar without restriction, advanced statistics and three extra themes.

Optional ads can restore a token, a life or an experience bonus. They never start on their own.