Click any square to start.
Every square either hides a mine or is safe. Clear a safe square and it shows how many of its eight neighbours are mined — clear one with no neighbouring mines and the whole surrounding region opens automatically. Use those numbers to work out where the mines are, flag them, and clear everything else to win.
Left-click clears a square, right-clickplants or removes a flag. On a phone, switch Flag mode on to place flags by tapping. The left counter shows mines remaining (total minus flags placed) and the right one counts the seconds.
Mines are laid after your opening click, avoiding that square and the eight around it — so the first move can never lose and always opens a region to work from. That's how the original behaves too, and it's why the game is about deduction rather than luck at the start.
Most positions can be solved by logic alone, but Minesweeper is not guaranteed solvable: occasionally two squares are genuinely indistinguishable and you have to pick one. That's part of the original game, not a bug here.