Most lost games of Minesweeper aren’t bad luck. They come from one of six mistakes, and the two biggest are guessing when there was a sure move somewhere, and flagging a square that wasn’t certain. The others are slips: forgetting that numbers count diagonals, forgetting the flags a number already has, guessing next to a number, and tapping in the wrong mode. Each one is below, with how to avoid it.
If you’re new, the rules and how to solve pages explain the ideas these mistakes go wrong on.
1. Guessing when there’s a sure move
When none of the numbers you’re looking at settles anything, it’s tempting to guess. But a sure move is usually still there, just not where you were looking. We played 200 of the game’s Classic (random) boards at each size and counted every time the two simple checks (a number with all its mines found, or with only its mines left hidden) ran dry:
| Field | Times the simple checks ran dry | A sure move was still there |
|---|---|---|
| Beginner | 135 | 108 (80%) |
| Intermediate | 435 | 352 (81%) |
| Expert | 1,659 | 1,485 (90%) |
Most of those moves come from comparing two numbers side by side, the 1-1 and 1-2 patterns.
How to avoid it: before you guess, go round the whole edge of the open ground once more, comparing each number with its neighbours. Guess only when nothing anywhere is certain. On the game’s default boards that never happens: there is always a sure move somewhere.
2. Flagging a square you’re not sure of
A flag on the wrong square is worse than no flag. It makes a number look finished, and then the honest next move, opening that number’s other squares, opens a mine.
We tested this on the same boards: three moves into each one, we flagged a safe square next to a number that still needed a mine, then kept making the simplest move the board seemed to allow.
| Field | A mine went off | A number visibly didn’t add up first |
|---|---|---|
| Beginner | 158 of 200 | 42 |
| Intermediate | 182 of 200 | 17 |
| Expert | 173 of 200 | 18 |
(On 1 Intermediate and 9 Expert boards, there was simply no move left.) And it’s quick: on Beginner, 136 of those 158 mines went off on the very next move. A wrong flag rarely gives you a warning.
How to avoid it: only flag a square a number proves is a mine. If you want to mark a square you suspect, keep it in your head instead.
3. Forgetting the diagonals
A number counts all eight squares around it, including the four diagonal ones. It’s easy to look only at the squares directly above, below and beside a number, and decide its mines must be somewhere else.
How to avoid it: for each number, run your eye round the full ring of eight squares, corners included, and count both the hidden squares and the flags.
4. Forgetting the flags a number already has
A number counts every mine around it, including the ones you’ve already flagged. A 3 with two flags beside it needs one more mine, not three. Reading it as a 3 hides the simple checks: if it has exactly one hidden square left, that square is its mine.
How to avoid it: take the flags off the number before you use it, as in tip 3. What’s left is what the number still needs.
5. Guessing next to a number
On Classic boards, when you do have to guess, the squares along the edge of the open ground feel like the natural place. They’re usually the worst. On boards that needed a guess, a typical square next to a number was a mine about 40% of the time, against 15 to 22% for squares away from all the numbers.
How to avoid it: guess away from the numbers, unless a number gives you better odds, like a 1 with seven hidden squares around it. Tip 6 has the full figures.
6. Tapping in the wrong mode
On a phone, a quick tap digs and a press held for a moment (about 0.4 seconds) flags. Switch to Flag and a tap flags instead. Forgetting which mode you’re in, or lifting your finger a moment too early, digs a square you meant to flag.
How to avoid it: glance at the Dig / Flag switch before a run of taps, and use one way of flagging consistently: either hold to flag, or switch modes, not a mix.
How to recover from a mistake
- A mine went off. There’s no undo, so the game is over. Look at the numbers around the mine before you start again: if one of them has a flag that doesn’t belong, that’s the mistake to learn from.
- A number doesn’t add up. It has more flags than its value, or not enough hidden squares for the mines it still needs. One of its flags is wrong. Take it off: press and hold it, or right-click it.
- Press Stuck? It checks your flags before anything else, and tells you when one of them is on a safe square.
- Stuck with no sign of a mistake? See when you get stuck.