Logic Puzzles Online: Free Slitherlink, Nurikabe, Kakuro and More
Japanese logic puzzles, played the way they should be.
12 Nikoli-style puzzle types with clean grids, pencil marks, undo and instant checking. Every puzzle has a unique solution reachable by logic alone. No guessing, no account.
12 puzzle types, thousands of verified grids
Pencil marks and undo
Mark candidates, cross out impossible edges and step back as far as you need. Nothing is lost on a misclick.Unique, verified solutions
Every grid is generated and then re-solved by a solver so it has exactly one answer and a logical path to it.Timer and progress
Your times, streaks and best per size stay in this browser. The daily puzzle of each type is the same for everyone, so you can compare with friends.About LogicPuzzles.io
Most of the puzzles here were popularised by the Japanese publisher Nikoli, whose pencil puzzles share one principle: a good puzzle is solved by deduction, never by trial and error. We generate and verify every grid so that it has exactly one solution and a logical path to it.
Each type comes with its rules, keyboard controls and a walkthrough of its first few deductions. Full rules for every puzzle are also on PuzzleRules.com.
FAQ
Yes. Every type and every size is free with no account and no ads. Progress and stats are saved in your browser.
No. Every puzzle is verified by a solver to have a single solution, and the Check button tells you whether your current marks are consistent with it.
Each type has one daily puzzle that is the same for every player and changes at midnight local time. Unlimited mode gives you a fresh random grid of the size you choose, as often as you like.
Yes. Grids scale to the screen width, a tap makes a mark and a long press makes the secondary mark, the same as a right click on desktop.
Each puzzle page has the rules, the controls and a few starting deductions. Complete rules and strategies are on PuzzleRules.com.