Slitherlink Puzzle Generator
Slitherlink is the loop logic puzzle: draw a single closed loop along the grid lines so that every numbered cell has exactly that many of its four sides used by the loop — cells without numbers impose no rule. Three difficulty levels from 4×4 to 6×6, draw on screen, and print or download as PDF with an answers option.
How to use the slitherlink maker
Pick a difficulty and a fresh puzzle appears instantly — every puzzle is different, and each one has exactly one solution.
- Reading the grid: each number says exactly how many of that cell's four sides your loop must use. A 0 means none of its sides are used; a 3 means three of them.
- Solving: draw one continuous closed loop. It can turn corners, but it can never cross itself, branch, or leave gaps. There is always exactly one way to draw it.
- Draw on screen: click a grid line to draw it, click again to cross it out, click again to clear. Check highlights anything wrong. Right-click crosses a line out directly.
- Printing: "Print / PDF" prints the blank puzzle — up to 2 per sheet. "Print Answers" prints the completed loop.
The rules of slitherlink
- Draw a single closed loop along the grid lines — it never crosses or branches.
- Every numbered cell must have exactly that many of its four sides used by the loop.
- Cells without a number impose no rule at all.
- The loop may touch itself at corners, but it must be one continuous, unbroken ring.
- There is exactly one solution, reachable by logic.
Frequently asked questions
What is a slitherlink puzzle?
Slitherlink is a logic puzzle by Nikoli (the Sudoku company). Draw a single closed loop along the grid lines so that every numbered cell has exactly that many of its four sides used by the loop. Cells without a number impose no rule at all. The loop must never cross or branch.
How do I draw the loop on screen?
Click any grid line between two dots to draw it, click again to cross it out as a note, and click a third time to clear it. Draw your loop, then press Check to see which lines are right. You can also right-click (or long-press) a line to cross it out directly.
Is the slitherlink puzzle generator free?
Yes. Every puzzle generator on this site is completely free and unlimited. There is no account, no sign-up and no watermark, and you can generate as many puzzles as you like.
How do I print a slitherlink puzzle or save it as a PDF?
Click "Print / PDF" to print the blank puzzle, or "Print Answers" for the completed loop. In the print dialog choose "Save as PDF" to download a file. You can print up to 2 puzzles per sheet.