Minesweeper

• Reveal every safe square to win. A number tells you how many mines touch that square, including diagonals.
• Your first opening and its neighboring squares are safe. Use Flag mode on mobile, right-click with a mouse, or press F on a focused square to mark a suspected mine.
• Tap an open number to reveal its neighbors when you have placed that many flags around it. Incorrect flags can still trigger a mine.
• The daily challenge is a 9×9 field with a fixed safe opening, shared by everyone for that UTC date. Random fields are not guaranteed to be solvable without guessing.
• Use the arrow keys to move between squares and Enter or Space to reveal. Larger fields scroll inside the board.

Read numbers together

If an open 1 touches exactly one unopened square, that square must contain a mine. Flag it, then check neighboring numbers again: if a number already has all of its mines accounted for, its other neighbors are safe. A flag is your own hypothesis, not confirmation from the game. Opening the neighbors of a number with incorrect flags can still lose the field.

When deduction stops

Compare overlapping groups of unopened squares before guessing. If one group must contain a mine and a larger overlapping group must contain exactly the same number, the extra squares in the larger group are safe. Random fields can still reach positions that require a guess. The safe first opening does not guarantee that every later move can be deduced. Start with a smaller field, and use Flag mode on a phone to mark mines without relying on a right-click.

Questions players ask

Do flags count as proof?

No. They are your own marks. Opening around a number with the right number of flags can still hit a mine if a flag is misplaced.

Must I flag every mine to win?

No. Reveal every safe square. The game marks the remaining mines once the field is cleared.

Is the first move always safe?

The first opening and its neighbours are safe. This does not guarantee a guess-free solution later.

Keep playing and learning

Practise a safe-square deduction, or try Nonograms for a picture made from row and column clues.