How to play Rainbow Sudoku
Rainbow Sudoku is Sudoku with colors instead of numbers. Your job is to fill every empty tile so that no color repeats in any row, any column, or any outlined box. Each puzzle has exactly one solution, and you can always reach it by logic alone, with no guessing.
Play today’s puzzle freeA tiny example
On an Easy 4×4 board there are four colors and four 2×2 boxes. In the top row below, red, yellow and green are already used, so the last tile must be blue.
The boards
| Level | Size | Regions |
|---|---|---|
| Easy | 4×4, 4 colors | rows, columns, 2×2 boxes |
| Medium | 5×5, 5 colors | rows and columns only |
| Hard | 6×6, 6 colors | rows, columns, 2×3 boxes |
| Expert | 9×9, 9 colors | rows, columns, 3×3 boxes |
Controls
- Tap a tile, then tap a color (or pick a color first and tap tiles to paint them). On a keyboard, use the arrow keys and the number keys.
- ✏️ Notes drops tiny color dots in a tile so you can track the colors it could still be. Placing a color clears that dot from the tile’s row, column and box.
- Undo, Erase and Hint are always there. A hint adds 15 seconds, and placing a color that clashes adds 3 seconds.
- The clock pauses whenever a menu or this kind of help is open, and the board is hidden while it’s paused.
Beginner strategy
- Last color standing. Look for a row, column or box with only one empty tile. The missing color goes there.
- Scan one color at a time. Pick a color and look at where it already appears. Each copy rules out its whole row, column and box. Often only one tile is left for it.
- Only one fit. For a single tile, list the colors its row, column and box already use. If just one color remains, place it.
- Use notes on Hard and Expert. When two tiles in a region can only be the same two colors, those colors are locked there and can be removed from the rest of the region.
Daily puzzle and scoring
Everyone in the world gets the same daily board for each size, refreshed at midnight UTC. Your score rewards speed and clean play, and fewer hints and clashes means more points. Add a nickname to join the daily, weekly and all-time leaderboards, keep a streak, and share a spoiler-free emoji grid of your result.
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