How to solve a Logicle grid
Read the starting cells, apply one rule at a time, and follow a complete practice-board walkthrough.
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Use a reason before placing a symbol
In Logicle, each six-cell row and column needs three suns and three moons. Three identical symbols cannot sit consecutively in either direction. An ≡ edge means the two cells match; ≠ means they differ.
Those are all the rules. Rows do not have to be unique, and a checkerboard appearance is not a requirement. Avoid importing extra rules from another logic game.
The example below is a fixed practice board, separate from the daily schedule. Rows count down from the top and columns across from the left. R2C3 means the cell in row 2, column 3; a dot is an empty cell.
Three deductions to look for
1. Complete a balanced line
If a row already has three suns, every remaining space in that row must be a moon. Count the whole column too: a placement can satisfy its row while breaking its column.
2. Prevent a third matching symbol
Two suns together force a moon immediately before or after the pair, if that cell exists and is empty. Two suns with one empty space between them force a moon in the gap. The same reasoning works with moons and vertically.
3. Follow an edge clue
A sun beside ≡ needs another sun across that edge. A sun beside ≠ needs a moon. If both cells are empty, the mark by itself does not tell you which symbol goes first; find information from the row or column.
The first move on this example
R1C1 must be a sun. R1C2 is a moon. The ≠ (different) clue between the cells requires the opposite symbol.
Place that symbol, then scan again. A filled cell can create a pair, complete a line's quota or give an edge clue a known neighbor. Treat the new information as a reason to revisit nearby lines rather than guessing somewhere unrelated.
Follow the complete solving order
Reveal all 20 deductions and the answer
- R1C1 = sun. R1C2 is a moon. The ≠ (different) clue between the cells requires the opposite symbol.
- R2C4 = moon. R2C2 and R2C3 are both suns. Another sun here would make three consecutive identical symbols in row 2.
- R2C5 = sun. R1C5 and R3C5 are both moons. Another moon here would make three consecutive identical symbols in column 5.
- R2C6 = moon. Row 2 already has three suns at R2C2, R2C3, R2C5. Its remaining cells must be moons to make three of each.
- R3C3 = moon. R2C3 and R4C3 are both suns. Another sun here would make three consecutive identical symbols in column 3.
- R3C4 = sun. R3C3 and R3C5 are both moons. Another moon here would make three consecutive identical symbols in row 3.
- R3C2 = moon. Row 3 already has three suns at R3C1, R3C4, R3C6. Its remaining cells must be moons to make three of each.
- R4C5 = moon. R4C3 and R4C4 are both suns. Another sun here would make three consecutive identical symbols in row 4.
- R4C6 = sun. Row 4 already has three moons at R4C1, R4C2, R4C5. Its remaining cells must be suns to make three of each.
- R1C6 = moon. Column 6 already has three suns at R3C6, R4C6, R6C6. Its remaining cells must be moons to make three of each.
- R1C3 = sun. Row 1 already has three moons at R1C2, R1C5, R1C6. Its remaining cells must be suns to make three of each.
- R1C4 = sun. Row 1 already has three moons at R1C2, R1C5, R1C6. Its remaining cells must be suns to make three of each.
- R5C1 = sun. Column 1 already has three moons at R2C1, R4C1, R6C1. Its remaining cells must be suns to make three of each.
- R5C2 = sun. Column 2 already has three moons at R1C2, R3C2, R4C2. Its remaining cells must be suns to make three of each.
- R5C3 = moon. R5C2 is a sun. The ≠ (different) clue between the cells requires the opposite symbol.
- R5C4 = moon. Column 4 already has three suns at R1C4, R3C4, R4C4. Its remaining cells must be moons to make three of each.
- R5C5 = sun. R5C3 and R5C4 are both moons. Another moon here would make three consecutive identical symbols in row 5.
- R5C6 = moon. Row 5 already has three suns at R5C1, R5C2, R5C5. Its remaining cells must be moons to make three of each.
- R6C3 = moon. R6C4 is a moon. The ≡ (same) clue between the cells requires the same symbol.
- R6C5 = sun. Row 6 already has three moons at R6C1, R6C3, R6C4. Its remaining cells must be suns to make three of each.
Each step is forced by information already on the board at that point. The sequence therefore reaches the solution without trying an unproved guess. You may find a different order; a useful solution explains why a cell is forced, rather than asking you to memorize the finished pattern.
Check carefully and use hints deliberately
Click an editable cell to cycle through blank, sun and moon. Arrow keys move between cells. Undo returns to your last local move while the board is still in progress.
A wrong Check board costs 25 points; a hint reveals one empty cell and costs 100. A solve starts from 1,000 points, so two incorrect checks and one hint leave 850. Points never go below zero. Review a filled cell's row, column and edge clues before requesting another check.
Try Unlimited practice for another board. If you want a walkthrough of the game you just played, open that date in the Logicle answers archive.
