Expert Slitherlink

Expert Slitherlink puzzles are 10×10 and need a contradiction: draw or cross an edge in your head, follow the rules a few steps, and if one breaks, the edge is the other way.

Mistakes: 00:00
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Start over?

This clears the board and the clock.

Expert puzzles need at least one of these techniques, and may use any easier one:

Contradiction
Leaving the marked edge empty breaks a rule a few steps later. So it must be a line.

How to play

Slitherlink is a loop puzzle on a grid of dots. Draw lines between neighbouring dots to make one single closed loop. A number in a cell tells how many of its four sides the loop uses; cells without a number can have any count.

Every Slitherlink here has exactly one solution and can be solved by logic alone. The grid grows from 5×5 at Easy to 10×10, and the level is set by the hardest technique the puzzle needs.

  • Draw one continuous loop along the grid lines, with no branches and no crossings.
  • A number counts how many of its cell's sides are part of the loop.
  • The loop never touches itself: every dot has two lines or none.

Playing on this site

  • Tap an edge to draw a line, tap again to cross it out, and once more to clear it.
  • Drag from dot to dot to draw several lines at once; a drag that starts on a line erases instead.
  • A number fades once it has all its lines.
  • Crosses are only a helper: the puzzle is solved as soon as the loop is complete.
  • Hint points out wrong lines and crosses first, then names the next technique and highlights the edges it decides.
  • Your puzzle is saved in this browser, so you can come back to it later.