Minesweeper

How to play

Minesweeper is a logic puzzle played on a grid of covered squares. Hidden beneath some of them are mines; every other square is safe. Click or tap a square to uncover it. If it is safe, it shows a number — that is exactly how many of the eight squares touching it contain a mine. A blank square means it touches no mines at all, and uncovering one automatically opens the whole connected blank area along with its numbered border, which is how a single click can clear a large region at once.

Mark suspected mines with a flag: right-click on a desktop mouse, or press and hold on a touchscreen. A flagged square cannot be uncovered by accident, so flagging is a way of protecting your deductions. You win the moment every safe square is uncovered, and you lose the moment you uncover a mine. The very first square you open is always safe — the mines are placed only after that click, and never under your starting square or the eight squares around it, so your opening move always opens a region and gives you something to reason about.

Three difficulties change the size of the board and the number of mines. Easy is a 9 by 9 grid with 10 mines, Medium is 16 by 16 with 40 mines, and Hard is 16 by 30 with 99 mines. When a numbered square already has the right number of flags around it, click that number again to open all of its remaining neighbours at once — a technique called chording.

Tips and strategy

Start on a corner or an edge rather than the middle. A corner has only three neighbours, so a safe opening click there is more likely to open a large blank area and hand you a wider spread of numbers to work with. Read the numbers as exact counts, not hints: a 1 touches exactly one mine, no more and no fewer, and that precision is what makes the puzzle solvable.

The most useful patterns appear where two numbers sit next to each other. A 1 beside a 2 along an edge usually tells you precisely which square is mined, and a 1 beside a 1 often means the two squares beyond them are safe. When you are certain a square is safe, open it rather than flagging everything you merely suspect — flags are subtracted from your mines-left counter, and a wrong flag can send you down the wrong path later. Watch that counter: when it reads zero, every remaining covered square is safe and you can open them all without risk.

Chording is the fastest way to clear a finished area. Flag a number's neighbours, then click the number itself and its remaining squares open together. Finally, accept that some boards end in a guess. On those, pick the square with the lowest chance of being a mine — usually one touching a number that is already satisfied — and move on rather than stalling.