Free online Slitherlink (also called Loop the Loop or Fences) with no ads and no sign-up. Pick a 5×5, 7×7, 10×10 or 15×15 grid or play the daily 7×7 puzzle, and every puzzle has exactly one solution. Your puzzle auto-saves on phone and desktop so you can pick it up later, and a leaderboard counts the puzzles you have solved and your fastest 10×10 times. Tap between two dots to draw a line, tap again for a cross mark, undo any move, and press Check to see whether your loop is closed and which marks are wrong. The rules: connect the dots into a single closed loop that never crosses or branches. A number in a cell says how many of that cell's four sides are part of the loop; empty cells can have any number of sides. When the whole loop is drawn and every number is satisfied, the puzzle is solved.
How to play
Touch: tap between two dots to draw a line, tap again for a cross, tap again to clear. The Line/Cross button chooses what a tap sets. Undo, Check and Zoom buttons below the grid. Keyboard: left click draws a line, right click sets a cross, arrows move the cursor, Tab flips it between horizontal and vertical, Space sets, Backspace clears, X toggles Line/Cross, C checks, U undo, Z zoom, Esc menu.
New in v1.0
First release: 5×5 to 15×15 grids and a daily 7×7, every puzzle with exactly one solution, tap-to-draw lines and crosses, undo, a Check button, auto-save and leaderboards.
