The full logical solve of the hard Slitherlink for September 15 to September 21, 2026, 12 × 12. 259 steps, 10 techniques, no guessing. Step through it, or jump to any step below.
The 0 at row 2, column 5 uses none of its four sides. Cross every one.
The 0 at row 3, column 1 uses none of its four sides. Cross every one.
The 0 at row 3, column 11 uses none of its four sides. Cross every one.
The 0 at row 5, column 11 uses none of its four sides. Cross every one.
The 0 at row 7, column 11 uses none of its four sides. Cross every one.
The 0 at row 9, column 1 uses none of its four sides. Cross every one.
The 0 at row 9, column 11 uses none of its four sides. Cross every one.
The 0 at row 11, column 3 uses none of its four sides. Cross every one.
The 0 at row 11, column 6 uses none of its four sides. Cross every one.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 3 at row 7, column 10 has exactly three sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 8, column 1 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 8, column 11 has exactly two sides that can still be lines. It needs all of them.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 3 at row 11, column 4 has exactly three sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 1 at row 10, column 5 has exactly one side that can still be a line. It needs it.
The corner dot has no other sides, so the 1 at row 1, column 1 uses both sides there or neither. Both would be two lines, so both are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 1 at row 1, column 1 has exactly one side that can still be a line. It needs it.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Every other side at that corner dot is ×, so the 1 at row 3, column 6 uses both sides there or neither. Both would be two lines, so both are ×.
The 2 at row 3, column 5 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Drawing this side would close a loop and leave other lines outside it. There is only one loop, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 1 at row 2, column 11 has exactly one side that can still be a line. It needs it.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 1, column 11 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 3, column 12 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 5, column 12 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 4, column 1 already has one line. Its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 2 at row 5, column 1 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
The 1 at row 1, column 5 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
A line runs into a corner of the 3 at row 1, column 7 from outside. That dot can take one more line, so the 3 can’t use both sides there. It uses the two sides away from that corner.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 3, column 2 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 2 at row 3, column 3 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 10, column 6 has exactly one side that can still be a line. It needs it.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 11, column 7 already has two lines. Its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 2 at row 10, column 8 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 3 at row 9, column 8 has exactly three sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 12, column 6 has exactly one side that can still be a line. It needs it.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 3 at row 12, column 9 has exactly three sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 3 at row 12, column 11 already has three lines. Its other sides are ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 11, column 10 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 10, column 11 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 9, column 10 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 8, column 8 has exactly two sides that can still be lines. It needs all of them.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 10, column 12 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
The 1 at row 3, column 6 already has one line. Its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 2 at row 4, column 5 has exactly two sides that can still be lines. It needs all of them.
The 1 at row 5, column 5 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 5, column 4 already has one line. Its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 4, column 6 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 2 at row 6, column 4 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 7, column 3 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 1 at row 8, column 6 already has one line. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Drawing this side would close a loop and leave other lines outside it. There is only one loop, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 2 at row 5, column 10 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 1 at row 6, column 9 has exactly one side that can still be a line. It needs it.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
Suppose this side were ×. Following the counting rules from there, some dot or number breaks. So it’s a line.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 2 at row 8, column 5 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
The 1 at row 6, column 6 has exactly one side that can still be a line. It needs it.
The 2 at row 7, column 6 has exactly two sides that can still be lines. It needs all of them.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Drawing this side would close a loop and leave other lines outside it. There is only one loop, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 5, column 9 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Drawing this side would close a loop and leave other lines outside it. There is only one loop, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
The 2 at row 4, column 9 already has two lines. Its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Suppose this side were a line. Following the counting rules from there, some dot or number breaks. So it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
This dot has no line and only one open side. A line there would stop dead at the dot, so it’s ×.
The 1 at row 2, column 8 has exactly one side that can still be a line. It needs it.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
Drawing this side would close a loop and leave other lines outside it. There is only one loop, so it’s ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.
This dot already has two lines. The loop can’t branch, so its other sides are ×.
A line ends at this dot, and only one side is still open. The loop can’t stop here, so it goes on that way.