Slitherlink is a logic puzzle where you draw a single closed loop by connecting dots. Numbers in cells show how many of the four edges around that cell are part of the loop.

Can I play Slitherlink on my phone?

Yes. Tap between dots to toggle lines. The board is fully responsive and works with touch input.

Slitherlink

Q: How do you play Slitherlink?

Click or tap between dots to draw lines. Numbers tell you how many edges around that cell belong to the loop. The loop must be closed with no branches and no crossings.

Q: What do the numbers mean?

A number 0-3 in a cell shows exactly how many of its four edges are part of the loop. For example, a 3 means three edges are drawn, a 1 means only one edge.

Play a free loop puzzle in your browser. Draw a single closed loop by connecting dots. Numbers show how many edges surround each cell. Start a new board anytime — no sign-up, no download.

5×5 0 edges drawn

How to play Slitherlink

1. Connect the dots with lines Click or tap between two adjacent dots to draw a line. Each line becomes part of your loop.
2. Follow the number clues Numbers 0-3 in cells tell you exactly how many of the four edges around that cell belong to the loop.
3. Form a single closed loop Your lines must form one continuous loop with no branches, no crossings, and no loose ends. Every drawn line must connect to exactly two others.

Slitherlink rules

One closed loop. No branches, no crossings, no loose ends.
Numbers are exact. A 3 means three edges, a 0 means none.
Empty cells have no constraint — their edges can be either way.
The loop can touch itself at corners but never cross.
A board is solved when the loop is closed and all number constraints are satisfied.

Every board is generated with a guaranteed solution. Start with 5×5 to learn the patterns, then try 7×7 and 10×10 for bigger challenges.

Slitherlink FAQ

What is Slitherlink?

Slitherlink is a logic puzzle invented by Nikoli. You draw a single closed loop by connecting dots. Numbers in cells indicate how many of the four surrounding edges are part of the loop.

How do you play Slitherlink?

Click between dots to toggle lines. Numbers tell you how many edges around that cell are part of the loop. The goal is a single closed loop that satisfies all numbers.

What do the numbers mean?

Each number 0-3 shows exactly how many edges around that cell belong to the loop. A 0 means no edges, a 1 means one edge, and so on. Blank cells have no constraint.

Can I play on my phone?

Yes. Tap between dots to draw or remove lines. The board scales to your screen and supports touch input.

Can the loop cross itself?

No. The loop can touch itself at corners (where four dots meet), but edges can never cross. Every point on the loop has exactly two connected edges.

How do I mark an edge as impossible?

Right-click (or long-press on mobile) to mark an edge with an X, indicating it cannot be part of the loop. This helps with deduction on harder puzzles.

Slitherlink

How to play Slitherlink

Slitherlink rules

Slitherlink FAQ

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