Slitherlink
Draw a single loop following the number clues.
The rules
How to play
- 01
The goal
Draw a single unbroken loop that runs along the grid edges and returns to where it started.
- 02
Read the numbers
Each numbered cell says exactly how many of its four surrounding edges the loop uses — 0, 1, 2 or 3.
- 03
No crossings
The loop never crosses itself or branches. Every dot it passes through has exactly two lines meeting there.
- 04
Blanks are free
Cells without a number place no constraint on their edges — let the numbered cells do the deducing for you.
- 05
Mark the gaps
Right-click an edge to mark it with an × when you know the loop cannot run there. It keeps the picture clear.
Play smarter
Six ways to close the loop
Start with 0s and 3s
A 0 forbids all four of its edges; a 3 in a corner forces a fixed pattern. Both hand you free moves.
Adjacent threes
Two 3s side by side lock the lines between and around them into a single forced shape.
Avoid early loops
If a line would close a small loop before every clue is met, that move has to be wrong.
Use × marks
Mark edges the loop cannot use. Ruling paths out is often as powerful as drawing them in.
Follow the dots
Every dot the loop reaches needs exactly two lines — a dot with one line forces a second.
Work the corners
Corner cells touch only two edges, so their clues resolve fastest. Anchor your loop there first.
Watch & learn
Two minutes to mastery
From the Intel desk
Reading for the curious
Slitherlink Puzzle: A Complete Beginner's Guide to Drawing Loops
Learn how to solve Slitherlink puzzles from scratch. Master the basic rules, follow our visual step-by-step tutorial, and discover essential patterns and strategies for beginners.
Slitherlink Strategies: Advanced Patterns for Faster Solving
Master advanced Slitherlink techniques: diagonal 3-3 patterns, parity analysis, corner deductions, and competition-level strategies. Transform your solving speed with proven pattern recognition.
Keep going
Where to next
Fresh every day
The Daily Slitherlink
One shared loop for everyone, every day. Build a streak and compare your solving time.
Go deeper
Rules & strategy guide
From corner threes to forbidden loops — the complete written guide with worked examples.
Beyond the grid
Explore all puzzles
Sudoku, Nonograms, Kakuro and fifteen more logic games await.