Sudoku on iqpi.io is an online number puzzle: play against a live opponent or in single-player. You can play for free or in a rated match with a Buy-in fee in IQPIC, and join Sudoku prize tournaments.
In the create form the variant is Classic. The mode with cages and sums is separate: Sudoku: Killer.
Below — how to create a game, board settings, how a win is decided, and where to find history.
Play runs in the personal account (lk).
Related: Sudoku: Killer, Rated games, Prize tournaments, Creating a tournament, Balance.
What this mode is
| Goal | Fill the grid by Sudoku rules (row, column, block) |
| Opponent | Live opponent or single-player |
| Match type | Unrated or Rated (Buy-in in IQPIC) |
| Tournaments | Yes — Sudoku discipline |
| Skill rating | Sudoku category |
On /game/create/sudoku, field Variant:
- Classic — this article;
- Killer → Sudoku: Killer.
There is no “play vs bot” mode like chess (Stockfish). There is single-player only.
Where to find what
| Area | URL | Purpose |
|---|---|---|
| Game pick | /game/create | Sudoku: vs human or solo |
| Settings | /game/create/sudoku | Variant, size, difficulty, error limit, time |
| Classic from home | /game/create/sudoku?variant=classic | Classic preselected |
| Solo | /game/create/sudoku?solo=1 | Single-player |
| Challenge | /game/create/sudoku?challenge_user_id=… | Challenge a player |
| Room | /game/sudoku/{hash} | Lobby and match |
| Spectator | /game/sudoku/{hash}/guest | Watch |
| History | /history/battles | Games |
| Tournaments | /tournaments | Catalog |
| Balance | /lk/balance | Buy-in and winnings |
Create a match vs a person
- Open
/game/create→ Sudoku vs a person (or/game/create/sudoku). - Set Variant to Classic.
- Set board size, difficulty, error limit, and game time.
- Choose match type: unrated or rated + Buy-in.
- Create the game →
/game/sudoku/{hash}. - Wait for an opponent or invite via challenge / link.
Fee details: Rated games.
Single-player
/game/create/sudoku?solo=1.- Variant Classic.
- Create and play immediately.
Solo is always unrated: Buy-in and challenge are unavailable.
Form settings
| UI field | Values | Meaning |
|---|---|---|
| Variant | Classic / Killer | Classic — this article |
| Board size | 6×6 or 9×9 | Cells per side |
| Difficulty | easy / medium / hard / expert | Higher = more empty cells at start |
| Error limit | 3, 5, or 10 | Wrong entries until loss |
| Game time | 1–60 minutes | Total time limit (default 15) |
Rated matches require a Buy-in in IQPIC.
Classic Sudoku rules
Fill every empty cell so that:
- digits do not repeat in any row;
- digits do not repeat in any column;
- digits do not repeat in any block (3×3 for 9×9; 6×6 blocks for the 6×6 board).
Given clues cannot be changed. Wrong input spends the error limit. In a duel, when a player hits the limit their board locks; if the opponent is already ahead on score the result is fixed at once, otherwise the game continues until a solve, time expiry, or Settle score.
In a duel, the winner is who first correctly completes the grid, or who has more points when time ends or the opponent is eliminated by the error limit (equal points — a draw). When one player has already finished, they see Game Over; Settle score is shown only to the player still in the game: they can end on current points without waiting for the party timer.
Tournaments
Sudoku tournaments are created via Creating a tournament: game type Sudoku, then variant, board size, difficulty, error limit, and game time. Solo and room Buy-in are hidden in tournament mode — bracket matches are tournament duels (the mode badge shows Tournament).
Catalog: /tournaments.