A grid with mines hidden under it. Open a cell and it tells you how many of its eight neighbours are live. Everything after that is deduction — the numbers are the only information there is, and they are enough.
The goal
Open every cell that isn't a mine. That's the whole win condition. You do not have to flag anything: a board cleared with no flags on it at all is a win, and the game plants the last flags for you when you get there. Open a mine and the run is over.
An opened cell shows one of three things. A number from 1 to 8 means that many of the eight cells around it are mines. A blank means none of them are — and because a blank is safe on all sides, the game opens its whole neighbourhood for you automatically, which cascades outward and is where most of the board comes from. A mine means you have lost.
The first tap is always safe
The mines are not placed until you have tapped. When you do, they are dealt into every cell except the one you tapped and its eight neighbours — so your opening move is guaranteed to be a blank, and guaranteed to open a region rather than a lone number. This is the modern fairness rule, and it means the opening tap is genuinely free: tap anywhere.
Because the mines are dealt around your first tap, tapping near the middle of the board opens more than tapping in a corner — a middle cell has eight neighbours cleared around it, a corner only three. It is the one move in the game where position is worth something for free.
Controls
- TapOpen a cell. This is the main control on a phone.
- HoldFlag a cell — press and hold for about half a second. Works whichever mode you are in, and it is the control most people end up using.
- Flag modeThe flag button in the top bar. Turn it on and a plain tap places a flag instead of opening. It lights up coral so you always know which one you are about to do.
- Tap a numberIf a number already has exactly that many flags around it, tapping it opens everything else touching it at once. See Chording below.
- Right-clickFlags, on a desktop.
- Arrow keysMove a cursor. Space opens, X flags.
- FToggle flag mode. N starts a new game.
A cell you have flagged will not open on a tap — that is the point of flagging it. To take a flag back, hold it again (or tap it in flag mode).
The three boards
| Board | Size | Mines | Density |
|---|---|---|---|
| Easy | 9 × 9 | 10 | 12% |
| Medium | 16 × 16 | 40 | 16% |
| Hard | 16 × 30 | 99 | 21% |
Hard is the traditional expert board — 480 cells and 99 mines — turned on its side. The usual layout is 30 wide by 16 tall, which on a phone gives you cells about 13 pixels across. Transposed it is the same board with the same difficulty in a shape that nearly matches a phone held upright, and it fits a 390-point screen whole with no scrolling. Nothing was made easier to fit the screen.
Each board keeps its own best time, stored on your device. The clock starts on your first tap, not when the page loads, so reading the board before you begin costs nothing.
Chording
This is the technique that turns Minesweeper from slow into fast, and it is worth learning properly. When a number has as many flags around it as its own value — a 3 with three flags touching it — every other cell touching that number must be safe. Tap the number and the game opens all of them at once.
The catch is exactly what it sounds like: the game trusts your flags. Chord on a 3 where one of those flags is wrong and you will open a mine. It is not a safety net, it is a shortcut you are vouching for. Tap a number whose flags don't add up and nothing opens — the neighbours flash instead, so you can tell "not satisfied yet" from "nothing there".
How to actually read a board
The two rules you will use constantly
Look at one number at a time and count the hidden cells touching it.
- If a number equals the count of hidden cells around it, every one of them is a mine. A 2 with exactly two hidden neighbours: both are mines. Flag them.
- If a number's flags already equal its value, every other cell around it is safe. Open them — or chord.
Most of any board falls to those two rules applied over and over. Work along the boundary between the opened region and the covered one; that edge is where all the information is. The middle of an untouched area tells you nothing.
The 1-2-1 and the 1-2-2-1
Along a straight wall of covered cells, a row reading 1 2 1 is always the same thing: mines under the two 1s, safe under the 2. A row reading 1 2 2 1 is mines under the two 2s, safe under the 1s. These come up constantly and recognising them by shape is much faster than counting them out each time.
Subtract one number from its neighbour
When two numbers share some of their hidden cells, compare them. If a 2 and a 1 sit next to each other and every cell the 1 can see is also seen by the 2, then the 2's extra cells must contain 2 − 1 = 1 mine, and if there is exactly one extra cell, that cell is a mine. This is the move that unpicks positions the two basic rules stall on.
Count what's left
Late in a board, use the mines-left read-out. If it says 3 and there are exactly three covered cells, they are all mines. If it says 0, everything still covered is safe and you can open it. This resolves endgames that look ambiguous cell by cell.
Guessing
Sometimes there is genuinely no deduction available and you have to pick. When that happens: prefer a cell touching a lower number, prefer corners and edges (they touch fewer cells, so there are fewer ways for them to be a mine), and prefer a guess that will open a lot if it is right. Do the counting first, though — most positions that look like a guess aren't.
Good to know
- Your best times and the board you are in the middle of are saved on your device. No account, nothing sent anywhere — and clearing your browser data clears both. Close the tab mid-game and it is still there tomorrow, clock and all.
- The eight numbers each have their own colour, so you read value off the colour before you read the glyph. The ramp goes cool at the bottom and hot through the middle, the same shape the original uses, re-cut to sit on a charcoal board instead of a grey one.
- Dragging on a board too big for the screen scrolls it and does not open or flag anything — so a scroll can never cost you a run.
- After a win or a loss, the result card can be stepped out of the way (See the board, or tap outside the card) so you can look at the finished grid.
- There is no timer pressure beyond the clock itself. Nothing on the board moves until you move it.