Why patterns beat recounting
Counting the neighbours of every number works, but it is slow and easy to get wrong. A pattern is a short sequence of revealed numbers whose mines are forced by the geometry, so recognising the shape gives you the answer without re-deriving it. Strong players do not calculate more than beginners; they recognise more. The shapes below cover most of what appears along an opened wall, and every one of them is a consequence of the same two rules.
Reduce before you match
Patterns describe the mines that are still unknown, not the numbers printed on the board. If a 3 already touches two flags, read it as a 1. If a 2 touches one flag, read it as a 1. Subtract satisfied numbers and mentally replace the printed digit with the remainder. Almost every report of a pattern that did not work turns out to be a flag that was already counted, a number that was already satisfied, or a hidden cell that was not actually on the same side of the wall.
1-2-1
Three numbers in a row against a wall, with hidden cells spanning one cell beyond each end. Each 1 needs exactly one mine and the 2 sees all three cells between them, so the only consistent layout puts mines under the two 1s and leaves the cell under the 2 safe. It is the most common pattern in the game and the first one worth learning.
1-2-2-1
The longer cousin. Four numbers in a row against a wall, with hidden cells extending one beyond each end. The two 2s share the middle cells, and satisfying both outer 1s forces the mines into the middle pair. All four outer cells are safe. If you remember only two patterns, make them this and 1-2-1.
2-3-2
A 3 between two 2s, with five hidden cells in a line. The 3 touches all five cells and needs three mines; the 2s on either side can only be satisfied if those three mines are the three middle cells. The two end cells are safe. This one is satisfying because the answer is complete: you can flag three cells and open two without any further checking.
1-2 and 2-1
These are partial patterns: they prove one mine and one safe cell rather than the whole row. With a 1 next to a 2 against a wall, the 1 can only cover one of the cells it shares with the 2, so the 2 must take its outside cell. That makes the outside cell a mine and the far end of the row safe. The mirror image, 2-1, proves the same thing on the other side. When the middle cells remain ambiguous, take the certain move and come back later.
1-1 and 3-2
Two adjacent 1s against a wall with hidden cells spanning the pair: the first 1 needs one mine in the shared cells, and the second 1 sees that same pair plus one extra cell, so the extra cell is safe. With a 3 next to a 2, the 3 touches exactly three hidden cells and therefore flags all three, which satisfies the 2 and makes its outside cell safe.
The single-neighbour rule
Every pattern above is a special case of two counting rules. If a number's remaining mine count equals the number of hidden cells it touches, all of those cells are mines. If its remaining count is zero, all of them are safe. The single-neighbour rule is the extreme case: a number touching exactly one hidden cell settles that cell immediately. Check corners and the ends of walls first, because that is where the rule fires most often.
When a pattern does not apply
Patterns are geometry, not magic. Rotations and mirror images are fine, but the numbers must be adjacent in a straight line and the hidden cells must all lie on the same side. If a number also touches hidden cells elsewhere, its count is shared between two frontiers and the simple reading no longer holds. Flags also have to be correct: a single misplaced flag breaks every pattern around it. If a shape refuses to resolve, stop matching and recount the numbers instead of forcing the pattern.
Patterns in a no-guess game
In No-Guess mode the answer always exists, but it may need more than a classic pattern. The board generator verifies each position with a solver that can exhaustively check the remaining frontier, which is stronger than a list of memorised shapes. Use patterns for speed and the Hint button when a position does not match anything you know; the hint uses the same solver and only marks cells that are provably safe.
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Start playing →Frequently asked questions
What is the 1-2-1 pattern in Minesweeper?+
Three numbers in a row against a wall with hidden cells extending past both ends. The mines sit under the two 1s and the cell under the 2 is safe.
What is the 1-2-2-1 pattern?+
Four numbers in a row against a wall. The mines sit under the two middle 2s, and the four outer cells are safe.
Do Minesweeper patterns work in every position?+
No. They only apply when the numbers are adjacent in a straight line and the hidden cells all lie on the same side. A number that also touches hidden cells elsewhere shares its count between two frontiers.
Why do patterns stop working when I place flags?+
Patterns count remaining mines, not printed numbers. Subtract satisfied numbers first: a 3 touching two flags behaves like a 1. A wrong flag will also break every pattern around it.
How do I practise Minesweeper patterns?+
Use the pattern trainer on the play page. It shows a small position, asks you to tap a cell you can prove is a mine or safe, and explains the rule behind the answer.
What is the most important Minesweeper pattern?+
1-2-1, followed by 1-2-2-1. Together they resolve most wall positions you will meet, and both are quick to recognise once you have seen them a few times.