Play Jigsaw Sudoku Online

Jigsaw Sudoku replaces the nine regular boxes with nine irregular regions. Thick cell borders show where each region bends. Rows and columns still contain digits 1 through 9 exactly once; now each outlined nine-cell shape must do the same. Trace a region across its bends before eliminating a candidate.

1. Read the given digits; these dark numbers stay fixed.
2. Select an empty square and use the number buttons to enter a candidate from 1 to 9.
3. Put each digit exactly once in every row and column.
4. Trace the irregular regions instead of square boxes.
5. Each of the nine irregular outlined regions contains the digits 1 through 9 exactly once instead of using ordinary square boxes.
6. Use Clear to erase an editable cell. Complete the board and check the variant rules to win.
7. Trace a thick boundary from cell to cell instead of assuming a regular three by three square. The irregular regions on this board bend slightly within each three-row band, but every one still holds nine cells. The boundaries are the only guide to region membership; a cell can sit across a boundary from its visual neighbor.
8. Follow the thick edges whenever you count a region. The thin lines still separate individual cells, while the thick borders define the irregular nine-cell groups. If your last move fills the grid but does not win, examine two identical digits inside one bent region before assuming the standard box rules apply. Use Clear to correct only your editable numbers.

• Every row contains the digits 1 through 9 once.
• Every column contains the digits 1 through 9 once.
• Each irregular outlined nine-cell region contains 1 through 9 once.
• Each of the nine irregular outlined regions contains the digits 1 through 9 exactly once instead of using ordinary square boxes.
• The region shapes replace standard square boxes. If two identical digits occupy different irregular regions but the same ordinary-looking three by three area, that alone is not an error. If the digits repeat in the same outlined region, the board rejects them, even when they appear in different conventional square boxes.

• Start with rows that have several given digits and list their missing values.
• Follow the thick boundaries carefully. Two adjacent cells may belong to different regions even when they sit inside the same visual three-column band.
• Check columns crossing a marked constraint before placing a digit.
• When a region has just one empty cell, fill its missing value and revisit the variant clue.
• A complete standard Sudoku grid can still fail a variant rule. Review every marked constraint before the final move.

• Sudoku: Practice the standard number-placement rules before trying a variant.
• Hyper Sudoku: Compare how a related puzzle uses regions, paths or tile placement.
• Sandwich Sudoku: Compare how a related puzzle uses regions, paths or tile placement.

• Each extra constraint adds a second way to narrow candidates.
• The number pad works with touch, mouse and keyboard focus.
• The variant rules reward scanning more than one region at a time.
• Jigsaw Sudoku trains careful grouping. The thick borders offer concrete structure, but your eye may keep trying to apply the familiar regular boxes. Follow one region's outline before making a box-based deduction. Every valid solution satisfies the irregular partition together with all nine rows and all nine columns.

Play Jigsaw Sudoku free in your browser. Start the interactive board above, use its on-screen controls and check the rules below when a deduction gets stuck. No download or account is needed.

Try another round of Jigsaw Sudoku on the board above. Start with the most constrained part of the grid, test each move against the stated rules, and use the reset control to try a new approach.

• Variant Sudoku reference