Free King-Size Jigsaw Sudoku with irregular polyomino regions. Daily challenge updated every day — plus 25 downloadable PDFs across five difficulty levels.
Two ways to play: solve today's challenge or download a PDF to print and solve at your own pace.
A new 16×16 Jigsaw Sudoku every day. View today's puzzle image, track your time with the built-in timer, download the PDF, or browse the full archive of past puzzles.
Open Daily Puzzle →25 printable King-Size Jigsaw Sudoku PDFs across five difficulty tiers. Filter by difficulty and download instantly — no account required.
Browse Downloads →Jigsaw Sudoku replaces the standard 4×4 boxes with irregular polyomino regions — jigsaw-shaped groups of 16 cells that twist and wind across the grid. Each region must still contain every digit from 1 to 16 exactly once, and standard row and column rules apply throughout.
The irregular shapes fundamentally change how you reason about the puzzle. Techniques like hidden singles and naked pairs must be applied through the lens of region membership rather than rectangular boxes — cells that look like neighbours may belong to different regions, and distant cells may share a region entirely.
In standard 9×9 or 16×16 Sudoku, the box regions are always aligned rectangles — easy to visualise at a glance. In Jigsaw, the regions meander across the grid. This makes it harder to intuitively track which cells are constrained together, which is precisely what makes it challenging. You must continuously refer back to the region boundaries when applying any elimination technique.
On a 16×16 grid with 16 irregular regions, the complexity compounds dramatically. The same techniques that work for Killer Sudoku — innies, outies, band analysis — apply here through region-sum reasoning rather than cage-sum reasoning.
Generous givens. Region shapes are relatively straightforward. Good introduction to irregular regions.
Fewer givens, more complex region shapes. Requires careful region tracking.
Highly irregular, interlocking regions. Multi-step deductions across regions and rows.
Winding, disorienting regions. Only for experienced solvers with strong pencil-mark discipline.
Maximum irregular complexity. These puzzles represent the hardest Jigsaw challenges available.