Logic grid puzzle rules
Read the clues, mark the grid, and figure out who goes where.
What is a logic grid puzzle?
You are given a scenario: a group of people (or objects), each with attributes spread across several categories. A pet owner puzzle might have three categories: names, pets, and favorite colors. Each person owns exactly one pet and has one favorite color. Your job is to figure out the complete matching using only the clues provided.
The tool you use is an elimination grid — a matrix where every possible combination of items has a cell. You mark cells as eliminated (X) or confirmed (✓) until every item is uniquely matched.
The rules
- Each item belongs to exactly one item in every other category. No sharing.
- Every clue is true and sufficient. The puzzle is solvable from the given clues alone — no guessing needed.
- Use the elimination grid to track what is possible and what is not. X means "this pairing is impossible," ✓ means "this pairing is confirmed."
- When you confirm a match (✓), eliminate every other option in that row and column. Each item can only match one thing per category.
Walking through an example
Three friends — Alex, Blake, Casey — each have a different pet (cat, dog, fish) and live in a different city (Austin, Boston, Chicago).
Clues:
- Alex does not have the cat.
- The dog owner lives in Boston.
- Casey lives in Austin.
- Blake does not live in Chicago.
Clue 3 gives a direct match: Casey → Austin. Mark ✓ in that cell, then X out Casey/Boston, Casey/Chicago, Alex/Austin, and Blake/Austin.
Clue 4: Blake ≠ Chicago. Combined with Blake ≠ Austin (from clue 3), Blake must be Boston. Mark ✓. That forces Alex → Chicago.
Clue 2: Dog owner = Boston = Blake. So Blake has the dog.
Clue 1: Alex ≠ cat. Since Blake has the dog, Alex must have the fish. Casey gets the cat.
Done. Three clue re-reads and a few eliminations solve the whole thing. Larger puzzles have more categories and items, but the technique is the same: eliminate, confirm, cross-reference, repeat.
Solving techniques
- Direct elimination: "A is not B" → mark X immediately.
- Direct assignment: "A is B" → mark ✓ and eliminate the rest of that row and column.
- Last remaining option: If a row has all but one cell eliminated, that cell must be ✓.
- Cross-referencing: If A=B and B=C, then A=C. Carry matches across all sub-grids.
- Conditional clues: "The person with the cat lives in a city that starts with B." You might not know who has the cat yet, but once you do, this clue immediately gives their city.
Difficulty levels
| Level | Grid | Notes |
|---|---|---|
| Easy | 3×3 (3 items, 3 categories) | Mostly direct clues |
| Medium | 4×4 (4 items, 3 categories) | More cross-referencing needed |
| Hard | 4×4 (4 items, 4 categories) | Conditional clues, deeper chains |
| Expert | 5×5 (5 items, 4 categories) | Multi-step deductions required |
| Einstein | 5×5 (5 items, 5 categories) | Full elimination logic, competitive |
Tips
- Process every clue on the first pass. You will often make more progress than you expect just from direct eliminations and assignments.
- After the first pass, re-read the clues. Conditional statements that seemed useless before may now apply.
- Check for rows and columns with only two options left. These are where the next breakthrough usually happens.
- Do not guess. If you feel stuck, there is a deduction you have missed. Re-read the clues one more time.
Frequently asked questions
What is a logic grid puzzle?
A puzzle where you match items across categories using clues and an elimination grid. Each item maps to exactly one item in every other category.
How does the elimination grid work?
The grid has rows and columns for every item. You mark X for impossible matches and ✓ for confirmed ones. When you confirm a match, eliminate everything else in that row and column.
Do I need math to solve these?
No. Logic grid puzzles are pure reasoning. You read clues, eliminate options, and deduce matches. Some clues reference numbers (ages, rankings) but the solving process is elimination, not arithmetic.
What if I get stuck?
Re-read every clue. Cross-reference positive matches across all sub-grids. Check for rows with only two remaining options. If truly stuck, use a hint.
Related puzzle rules
- Deduction puzzle rules — Clue-based puzzles without a grid
- Pattern puzzle rules — Find the missing element in a sequence
- Cryptogram rules — Decode substitution ciphers letter by letter
Ready to play? Start with an easy puzzle or pick your difficulty.