In jigsaw sudoku, also sold as irregular sudoku or squiggly sudoku, the thick lines no longer draw neat boxes. Each grid on this page gets new region shapes from our generator, and the jigsaw sudoku solver confirms it has exactly one answer before you see it.
How to play
Fill every row, every column and every outlined region with the digits 1 to 9, once each. Regions are any connected group of nine squares, so they snake across the grid and reach into rows and columns that a box would never touch. Tap a square, then a digit; Pencil writes small candidates.
Levels
Easy: 36 given digits, singles only. Medium: as few clues as possible, at least one Medium step such as a pointing pair, nothing harder; these come from a bank of grids we generated and checked, because they take a few seconds each to find. Hard: minimal clues with Hard, Expert or Master steps, never trial and error.
Jigsaw tips
- Law of leftovers: take any set of whole rows, say the top two. The regions that lie completely inside them use some of their 18 squares; the squares left over in those rows must hold exactly the same digits as the parts of regions that stick out below. This trick is unique to jigsaw sudoku and cracks many grids.
- Long thin regions are your friends: a region that stretches along one row behaves like a pointing line for every digit it must place there.
- Check region membership twice before placing. Most mistakes in jigsaw sudoku come from misreading a border.
Hints and records
Hint explains the next deduction in words and highlights the region or line it uses; a wrong digit is removed first. Check and Show mistakes compare your digits with the answer. Games, best and average times and your daily streak stay in this browser, per level. The same techniques are explained on the sudoku techniques page; if you like this, try samurai sudoku or the classic sudoku online.
Solver tested . Found a problem? Tell us.
Questions
Are jigsaw sudoku and irregular sudoku the same?
Yes. Jigsaw, irregular, squiggly and geometric sudoku all mean a 9 by 9 sudoku with irregular regions instead of boxes.
What is the law of leftovers?
Pick whole rows or columns. The squares of those lines that are not in regions fully inside them must hold the same set of digits as the squares of those regions that lie outside the lines.
Why does the medium level load from a bank?
Medium jigsaw grids are rare among random ones, so finding one can take several seconds. We generated a set in advance and our tests check every one for a single answer and the right rating.
Is the daily jigsaw sudoku the same for everyone?
Yes, one grid per level per day, chosen from the date by our own generator or bank.