Logic Grid Puzzle Generator
Fresh Einstein-style logic puzzles with a grid to work on. Every puzzle is checked to have exactly one answer, and every clue is proven to be needed.
Logic grid puzzle
Your working
Click a cell to cycle it: blank → ✓ → ✗. Nothing here is checked against the answer, it is just somewhere to think.
The answer
How to solve one, and how these are made
- Every clue matters. After a puzzle is generated, each clue is removed in turn to see whether the answer is still forced. Anything that can go, goes — so if you are stuck, there is a clue you have not used properly rather than one that was padding.
- Cross out as much as you tick. A negative — "not the green one" — usually does more work than a positive, because it applies to a whole row at once.
- Chain your facts. If Ana is 2nd and 2nd has the tea, then Ana has the tea, even though no clue says so. That step is where most people stall, and it is the same rule the solver here leans on hardest.
- "Next to" and "earlier than" cut the ends off. Someone who comes earlier than someone else cannot be last; someone exactly three apart in a row of four must be at one end or the other.
- The puzzle is checked to have exactly one answer before you see it — not merely to be consistent with the clues.
How to use
- Pick a theme and a size, then read the clues.
- Click cells in the grids to tick or cross as you work.
- Press Show the answer when you are done, or stuck.
Frequently asked questions
Could a puzzle have more than one answer?
No, and it is checked rather than assumed. A real solver runs over the clues and counts solutions, and a set that allows two arrangements is thrown away. Clues that are merely true are easy to produce — clues that force one answer are the actual work.
Are any of the clues padding?
None of them. After generating, each clue is removed in turn to see whether the answer is still forced, and anything that can go, goes. So if you are stuck, there is a clue you have not squeezed properly rather than one that was never going to help.
Where do most people get stuck?
Chaining. If Ana is 2nd and the person who is 2nd has the tea, then Ana has the tea — even though no clue says so. That step is easy to miss on paper and it is the single rule the solver here leans on hardest.
What do the “next to” clues really tell me?
More than they look. Someone who comes earlier than someone else cannot be last, and the other cannot be first. A pair exactly three apart in a row of four must be at the two ends. Those eliminations are usually worth more than a positive clue.
Is the working grid checked as I go?
No, deliberately. It is somewhere to think rather than a marking scheme, so a wrong tick will not be corrected and will not give anything away. Reveal the answer when you want it.
How hard are the sizes?
Three of each is a gentle introduction with about five clues. Four is a normal puzzle. Five of each is genuinely hard and takes a full grid of working — it usually needs around ten clues, every one of them load-bearing.
🔒 This tool runs entirely in your browser. Nothing you enter is uploaded, logged, or stored.