Beginners at Minesweeper do arithmetic. Everyone else does pattern recognition. The arithmetic is the foundation, but nobody good is computing it square by square — they are seeing shapes they have seen a thousand times before.
Here are the shapes worth learning, and the two rules they all come from.
The two rules everything is built on
Rule one. If a number equals the count of unopened squares touching it, all of those squares are mines.
Rule two. If a number equals the count of flags touching it, every other square it touches is safe.
That is all of Minesweeper. Every pattern below is one of these two rules applied to a shape common enough to memorise.
The 1-2-1
Along the edge of an opened region:
? ? ?
1 2 1The mines are under the two ones, and the square under the 2 is safe.
Why: the 2 touches all three unknowns. The left 1 touches only the first two, and the right 1 only the last two. If the middle square held a mine, both ones would be satisfied and the 2 could not reach two. So the middle is empty and the outer two are mines.
This is the single most common pattern on a real board and it is worth being able to see instantly.
The 1-2-2-1
? ? ? ?
1 2 2 1Mines under the two 2s. The squares under the 1s are safe — the mirror image of the 1-2-1, and it turns up almost as often.
The 1-1 running away from a wall
? ? ?
1 1 XWhen a pair of ones sits with a wall or an opened region behind them, the third square along is safe.
Why: the two unknowns nearest the first 1 must contain exactly one mine. The second 1 also touches those two squares, so its mine is already accounted for — nothing is left for the third square.
This pattern is how you make progress along the border of a region when nothing else is forced, and it is the one beginners most often miss.
The corner 1
A 1 in a corner touching exactly one unopened square: that square is a mine. Trivially rule one, but corners are easy to overlook because they sit at the edge of your attention.
Counting the remainder
Late in a board, the mine counter becomes a pattern in itself. If you have flagged 68 of 70 mines and there are exactly two unopened squares left in one region and none elsewhere, both are mines, regardless of what any individual number says.
This global constraint solves positions that look locally ambiguous, and it is where a lot of “impossible” boards turn out to be solvable after all.
Chording is not a shortcut, it is the game
Once a number has the right count of flags around it, clicking it opens everything else it touches.
The risk is exactly zero — you are acting on information you already proved — and the speed difference is enormous. An expert board opened square by square takes several minutes. The same board played with chording takes well under two.
If you take one habit from this page, take that one. On our version chording works on any satisfied number, and the first click of every game is guaranteed safe, so there is no cost to opening aggressively.
When you genuinely have to guess
Some boards end in a real coin flip. Mine placement is random, so this is unavoidable, and no amount of staring will produce a deduction that is not there.
When it happens, guess at a corner or an edge. Those squares touch fewer neighbours, so a wrong guess loses less information and a right one constrains the remaining board more tightly. It is a small edge, and over a hundred games it is a real one.
The other half of guessing well is knowing when you are guessing. Players who lose most often are not unlucky — they are taking coin flips on squares where a deduction was available three numbers away.