SudokuSwap is a daily puzzle game that reinvents sudoku around a single action: the swap. Instead of filling an empty grid with numbers, you're handed a completed sudoku that has been scrambled, and your job is to put it back together by swapping pairs of tiles. This guide covers the rules, how to read the board's colors, and the strategy that separates a slow solve from a perfect five-star one.
Play today's puzzles →Every puzzle begins as a valid, fully solved sudoku — each row, column, and 3×3 box contains the digits 1 through 9 exactly once — that has then had its tiles shuffled. You restore the solution by tapping one tile and then tapping a second tile to swap their positions. There is always a correct arrangement, and the puzzle tracks how many swaps you use, because your score depends on solving it efficiently, not just correctly.
The colors are the whole game. After every swap the board recolors itself to show how close each tile is to home:
A green tile is already in its correct position. Green tiles lock: you can't move them, and you don't want to. When the whole board is green, you've won.
A yellow tile holds a digit that belongs somewhere in that same row, column, or 3×3 box — just not in its current cell. Yellow is your most valuable clue, because it tells you where a tile needs to go without making you guess across the whole grid.
A plain (uncolored) tile belongs somewhere further away — a different row, column, and box entirely. These take the most planning to place.
The strongest opening move is the perfect swap: two tiles that are simply sitting in each other's correct spots. Swapping them turns both tiles green in a single move, and SudokuSwap celebrates the moment with an animation. Scan the board for these pairs first — every perfect swap you find fixes two cells for the price of one, which is the foundation of an efficient solve.
A quick way to spot them: pick a yellow tile, note the digit it needs, and check whether the cell that digit belongs in is holding the very tile your first one wants. If so, that's a perfect swap.
Once the easy pairs are gone, the tiles that remain usually form cycles: tile A sits in B's spot, B sits in C's spot, and C sits in A's spot. A three-tile cycle can't be fixed by a single perfect swap — it always takes exactly two swaps. The efficient approach is to plan both moves before you touch anything: swap two of the three tiles so that at least one lands on green, then the final swap resolves the rest. Moving tiles one at a time without seeing the cycle is the most common way players waste swaps.
Every board has a known minimum number of swaps — the fewest moves in which it can possibly be solved. Match that minimum and you earn a perfect five-star rating. Each small band of extra swaps beyond the minimum lowers your rating by a star. So the real challenge of SudokuSwap isn't whether you can solve the board — it's how few moves it takes. Before every swap, ask a simple question: does this move bring at least one tile home (to green)? A swap that greens neither tile is almost always a wasted move, and the game quietly tracks your swap accuracy so you can watch it improve over time.
If you get stuck, the hint button will highlight a useful swap for you. Hints come at a cost: each one adds two swaps to your count, which can pull down your star rating. Treat hints as a way to keep a frustrating board moving rather than a default crutch, and you'll keep your ratings high.
SudokuSwap publishes three fresh puzzles every day, one at each difficulty. Easy boards start with more tiles already green and resolve in short chains of swaps. Medium and hard boards start further from solved and weave longer cycles together, so planning several moves ahead matters much more. If you're new, start on easy to get a feel for reading the colors, then work your way up.