What is it?
Fill empty cells without repeating a number in a row, column or 3×3 box. Use pencil notes to track candidates as you practice or compete.
Play free in your browser without installation. Solo practice needs no account; sign in with your GameNow account for online matches, rankings and friends.
A sudoku game for climbing from Easy to Expert without guessing: every puzzle is checked to be solvable by logic. Stuck? A hint names the technique and highlights the cells behind it, so sudoku strategy sinks in, not just the answer. Signed in, sudoku online free daily boards match for everyone, ranked per level.
GameNow Sudoku decides how hard a puzzle is by solving it the way a person would. A built-in solver knows twelve named techniques, from Naked Single to Swordfish, and always tries the easiest one first. A puzzle's level comes from the hardest technique it needs plus the total amount of work, and every clue removed while the puzzle is built is checked against that solver, so no puzzle ever requires guessing.
Every puzzle grows from a single seed number. Today's puzzle takes its seed from the UTC date and the level, so everyone who opens Hard on the same day gets the same grid, and both duel players build their boards from one shared seed. Your progress is saved as that seed plus the moves you made, and the daily ranking replays those moves on the server before it accepts a time.
Hints explain instead of just filling a cell: they name the technique, light up the cells that prove it, and can tidy your notes in one step. After the puzzle you can revisit those exact positions as short quizzes.
Gameplay video and screens
How to play
- Pick a level (Easy, Normal, Hard, Expert) to solve alone. Signed out, choosing one in the level box at the top opens a new practice puzzle at once (not ranked); signed in, pick it under "Today's puzzle" in the lobby and press 'Play'. To face a person, choose a duel level and press 'Find opponent'.
- Click (tap) a cell or move with the arrow keys, then enter a digit with the number buttons or keys 1–9.
- Write candidates as notes (toggle with the Notes button or N, or use Shift+digit). A wrong digit shakes the cell, gets a wavy underline and counts as a mistake. Undoing it does not take the mistake back.
- When solving alone and stuck, Hint (3 per puzzle) shows the technique, the reason and the cells behind it. Apply it or close it.
- The puzzle ends when every cell is correct. Solo records your time; a duel records the result.
Modes
- Today's puzzle
- Signed-in players get four puzzles a day, one per level, identical for everyone; a new set starts at 00:00 UTC. A hint-free solve you submit goes onto that level's ranking once the server has replayed it, and rankings are kept for 30 days.
- Practice puzzle
- Choosing a level while signed out, or pressing Play again after any solo puzzle, deals a fresh puzzle at that level with the same tools. Its time only updates the personal best stored on your device.
- Duel
- Two signed-in players who chose the same level get the same puzzle, with no Undo or Hint, only Resign. If the 12 minutes run out, more correctly filled cells wins, then fewer mistakes; otherwise it is a draw.
Good to know
- "Today's puzzle" ranks everyone who solved the same level that day by time. A puzzle solved with hints is not ranked.
- Solo only counts mistakes and never ends the puzzle. In a duel, three mistakes lose on the spot.
- Solving well in a duel automatically sends sabotage that locks or hides your opponent's cells. You can still write notes in a locked cell.
At a glance
- Genre
- Puzzles & cards
- Players
- 1–2
- Price
- Free
- Available languages
- Korean · English · Japanese · Chinese · Spanish
- Platform
- Web browser (no install)
More on the game site
Further reading
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