How to play Slitherlink
Draw a single closed loop between dots. Every number tells you exactly how many of its four edges the loop uses.
The rules
- Draw one loop. Connect neighbouring dots with line segments until the board contains one continuous loop.
- Match the clues. Each number tells how many of the four surrounding edges belong to the loop.
- No branches. The line cannot branch, cross itself, or end halfway. Every used dot has exactly two line edges.
- Use crosses. Mark impossible edges with crosses to keep the loop clean on harder boards.
Play a board
A real Slitherlink board, playable here. Tap an edge between two dots to cycle blank, line, ruled out. Break a rule and the page names it.
- One closed loop. The line never branches and never splits in two.
- Match the numbers. A number says how many of that cell’s four edges the loop uses.
- Empty cells are free. A cell without a number can have any number of edges.
Where to start
Every 0 is a gift: cross out all four of its edges immediately, and the neighbouring clues suddenly have fewer places to go.
Look for a 3 next to a 0 — the three edges are forced at once. Two 3s side by side are just as strong: the edge between them belongs to the loop, and so do the outer edges of both.
Corners are worth checking early, because a clue in a corner has fewer possible edges than the same clue anywhere else.
Slitherlink on your phone
The same puzzle on iPhone and Android, including a board part-way through.
Where to play Slitherlink
Slitherlink is on iPhone and iPad. It is not on Google Play yet.
