Minesweeper guide
How to play Minesweeper: the rules and the patterns that solve most boards
Every number tells you how many of the squares touching it hide a mine. Open the squares that must be safe, flag the ones that must be mines, and you win when every safe square is open. Two simple rules and three small patterns (1-1, 1-2 and 1-2-1) solve nearly everything.
In the pictures below, teal squares are unopened, a square ringed in green is safe, and one ringed in red is a mine.
The rules
The board is a grid of unopened squares, and some of them hide mines. Opening a square shows one of three things:
- A number, 1 to 8. That many of the squares touching it hide a mine. Diagonals count, so a square in the middle of the board touches eight others, one on an edge touches five, and a corner touches three.
- A blank. None of its neighbours is a mine, so the game opens them all for you, and carries on through any more blanks it finds. This is how one tap can open a large area.
- A mine. The game is over.
You can mark a square you believe is a mine with a flag. Flags are notes for you: you don't have to place any. You win when every square that isn't a mine is open.
| Level | Board | Mines | Share of squares |
|---|---|---|---|
| Beginner | 9 × 9 | 10 | 12% |
| Intermediate | 16 × 16 | 40 | 16% |
| Expert | 30 × 16 | 99 | 21% |
Your first square is always safe. In Yuzool's Minesweeper the squares touching it are safe as well, so the first tap always opens an area to work from.
The two basic rules
Most of a game is these two rules, used over and over. For any number, count its unopened neighbours and the flags already beside it.
- All mines. If a number still needs as many mines as it has unopened neighbours, every one of them is a mine. A 1 with a single unopened neighbour: that neighbour is the mine.
- All safe. If a number already has all its mines flagged, every other unopened neighbour is safe.
Each rule feeds the other. A new flag satisfies neighbouring numbers, which makes squares safe, which opens new numbers.
The 1-1 pattern
Two 1s side by side, starting from a wall or an open edge, with a row of unopened squares along them. The first 1 touches two unopened squares, so its mine is in one of those two. The second 1 touches those same two squares plus a third. Its one mine is already in the shared pair, so the third square is safe.
The 1-2 pattern
A 1 next to a 2 along a row of unopened squares. The 2 needs two mines. At most one of them can be in the squares it shares with the 1, because the 1 only allows one mine there. So the other mine must be in the 2's remaining square: the square on the far side of the 2 is a mine.
The same reasoning works with bigger numbers once you subtract the flags already placed. A 3 with one flag beside it behaves like a 2, and a 2 with one flag behaves like a 1. Always think in terms of how many mines a number still needs.
1-2-1 and 1-2-2-1
These are the 1-2 pattern used from both ends, and they come up so often that it pays to know them by sight.
Worked example
Take 1-2-1 against a straight edge. From the left, the 1 and the 2 make a 1-2, so the right-hand square is a mine. From the right, the other 1 and the 2 make a 1-2 the other way, so the left-hand square is a mine. That is both of the 2's mines, so the middle square is safe.
Chording
When a number has all its mines flagged, you can open the rest of its neighbours in one move by clicking the number itself (on a phone, tap it). This is called a chord. It saves a lot of taps, and it is how quick players clear a board.
- A chord only works when the flags beside the number match the number exactly.
- A chord trusts your flags. If one is on the wrong square, the chord opens a mine.
- In Yuzool's Minesweeper, a middle click also chords, and so does a right click on a number.
Counting mines at the end
The counter shows how many mines are left unflagged. Near the end of a game it is a clue in its own right.
- None left. If the counter reads 0 and your flags are right, every unopened square that remains is safe.
- As many mines as squares. If three squares are left and three mines, they are all mines, and you have already won.
- A sealed-off corner. If the numbers on the open edge account for all the remaining mines, squares that none of those numbers touch must be safe. And if they account for all but one, a lone sealed-off square holds it.
Worked example
Two mines remain. A 1 on the left of the gap needs one more mine among two squares, and a 1 on the right needs one more among two different squares. Those two numbers use up both mines between them, so a fifth unopened square in the corner, touched by neither, is safe.
Guessing, and no-guess boards
On a classic, fully random board you can reach a position where no rule applies: two squares, one mine, and nothing to tell them apart. Then you have to guess. If you must:
- Check the mine counter first. Counting often settles what looks like a guess.
- Prefer the guess with the best odds. A square beside a 1 with four unopened neighbours is a 1 in 4 risk; one of two squares sharing a mine is 1 in 2.
- Take forced 50-50s early. If a guess cannot be avoided, there is nothing gained by clearing the rest of the board first.
A no-guess board is one that has been checked by a solver before you see it: from the first square, logic alone always finds a next step. Yuzool's Minesweeper deals no-guess boards by default, checked with exactly the rules on this page (the two basic rules, pairs of numbers, and counting). If you get stuck, the Hint button points at a square that can be worked out and tells you why in a sentence.
Common mistakes
- Forgetting diagonals. A number counts all eight neighbours, not just the four beside it.
- Flagging on a hunch. A wrong flag misleads every number round it, and a chord on it ends the game. Flag only what you have proved.
- Reading a number as its face value. Subtract the flags first. A 3 with two flags is a 1.
- Guessing when you didn't need to. Look along the whole edge of the open area before you give up. There is usually a 1-1 or a 1-2 somewhere.
- Ignoring the counter. The last few squares are often decided by the number of mines left.
Questions
How do you play Minesweeper?
Open squares to find the numbers. Each number says how many of the eight squares touching it hide a mine. Use the numbers to work out which squares are safe to open and which to flag. You win when every square without a mine is open.
What do the numbers mean in Minesweeper?
A number counts the mines in the squares touching it, including diagonals: up to eight squares in the middle of the board, five on an edge and three in a corner. A blank square has no mines round it.
Is the first click in Minesweeper always safe?
In most modern versions, yes. In Yuzool's Minesweeper the first square and all the squares touching it are free of mines, so your first tap always opens an area.
Do you ever have to guess in Minesweeper?
In classic Minesweeper, sometimes: some boards end in a 50-50 that no logic can settle. No-guess boards are made so that logic always finds a next step. Yuzool's Minesweeper deals no-guess boards unless you pick Classic.
What is chording in Minesweeper?
Chording is clicking a number that already has all its mines flagged, which opens every other square round it at once. It is the main way fast players save clicks.
What is 3BV in Minesweeper?
3BV (Bechtel's Board Benchmark Value) is the fewest left clicks needed to clear a board without flags: one for each opening and one for each number that is not on the edge of an opening. It measures how hard a board is, and 3BV divided by your clicks is your efficiency.