Technique 1 of 8 · Start here
Find a mine without guessing
The guide and all minesweeper techniques
Minesweeper techniques
- 1Finding certain minesStart here
- 2Finding safe cellsStart here
- 3Flagging and chordingCore technique
- 4Comparing neighbouring numbersShared cells
- 5Subtracting known minesSimplifying clues
- 6The 1–2–1 patternRecognising patterns
- 7The 1–2–2–1 patternRecognising patterns
- 8Using the remaining mine countFinishing a board
A number counts mines in the cells touching it, including diagonals. Start by counting those neighbours, not by looking for a familiar shape.
When a clue needs two mines and has only two covered neighbours left, both are mines. There is no choice about where they go. A flag records that deduction; placing a flag does not make it true.
Example 1: Two places for two mines
Step 1 of 3
Start with the lower-left 2. Count its covered neighbours, including the diagonal.
The lower-left 2 touches both covered cells. Its other neighbours are already open or beyond the board edge, so those two cells are all it can be counting.
Each cell can hold at most one mine. Both must therefore be mines. The second 2 agrees, but the first clue was enough to prove them.
Work inside the solid frame. Every possible mine neighbour of these clues is inside it. Cells beyond the frame are background, not revealed zeros or extra clues.
Flags are proved mines. A tick marks a cell proved safe; its number is not shown.
Blue-ringed numbers are the clues to compare. Shading marks the cells being discussed.
Try it yourself
Try the reasoning yourself. Choose an answer to see the explanation.
The middle clue counts three mines. Account for every covered cell it touches.
Practice only: no clock, saved game or hint charge.
Task 1 of 1: Flag all cells proved to be mines.
Choose a cell on the board.
Work inside the solid frame. Every possible mine neighbour of these clues is inside it. Cells beyond the frame are background, not revealed zeros or extra clues.
Practice close-up: rows 1–4, columns 1–4.
Flags are proved mines. A tick marks a cell proved safe; its number is not shown.
How to spot it faster
- Look for a number with only a few covered neighbours.
- Include diagonals. A cell touching a corner of the number still counts.
- If some mines are already proved, subtract those before comparing the count with the cells left.
Common mistakes
Flagging the same number of cells at random
A 2 does not tell you which two cells are mines when it still touches three or more possible places. Count the available cells before flagging.
Counting only above and below
A number can touch eight cells. Missing a diagonal can turn a choice into a false certainty.
Questions
Further reading
Try it
Open the marked safe start in solo play. Look for one number whose covered neighbours are all accounted for, and explain why each flag is certain before placing it.
Play solo Minesweeper