Minesweeper patterns that save you from guessing

Most of a Minesweeper board can be solved with a handful of recurring patterns. Learn to spot them and your times will drop fast.

The two basic rules

• If a number has as many hidden neighbours as its value, all of them are mines.
• If a number already has that many flags around it, all its other hidden neighbours are safe. Click the number to open them all at once (chording).

Pattern 1-2-1

Three numbers in a row along a straight edge of opened squares, reading 1-2-1, with three hidden squares beside them:

? ? ?
1 2 1

The mines are next to the two 1s, and the square next to the 2 is safe. (If the middle square were a mine, one of the 1s would need a second mine.)

Pattern 1-2-2-1

? ? ? ?
1 2 2 1

The mines are next to the two 2s; the squares next to the 1s are safe.

Pattern 1-1 from a wall

When a 1 sits against the board edge (or against already opened squares) and the next number along is also a 1, the mine of the first 1 must be in the two squares they share. So the third square touched only by the second 1 is safe.

Pattern 1-2 (the "reduced" 2)

If a 1 and a 2 sit side by side, the 2 needs one more mine than the 1 can supply from their shared squares. That extra mine must be in the square that only the 2 touches. Flag it.

Subtracting numbers

Many patterns are really one idea: subtract flags and known mines from a number to get its remaining value. A 3 with one flag already beside it behaves like a 2. Re-read the board with reduced values and the 1-2-1 and 1-1 patterns appear everywhere.

When you must guess

• Guess early rather than late – losing at the start costs less time.
• Prefer squares that would open new information, such as squares away from the frontier.
• Corners have fewer neighbours, so a safe corner square is more likely to open a zero.

Speed tips

• Use chording constantly; it is much faster than single clicks.
• Only flag mines you need for chording.
• Start Expert boards in the middle, where a first click is likely to open a large area.

Put the patterns to work in Minesweeper.