The first click is never a mine
The mines are laid after you click, around wherever you clicked, keeping that square and the eight touching it clear. So an opening click always opens a region and gives you something to reason from.
Implementations that lay the mines before the first click end perhaps one game in eight instantly, through no mistake at all. That is the reason people come away thinking Minesweeper is mostly luck. It is not — but it has to be dealt a fair opening to show that.
Flags, and opening a square with a number on it
Right-click plants a flag; on a phone, press and hold for a moment. The counter beside the board is the mines remaining minus the flags you have placed, so it goes negative if you over-flag.
Clicking a number that already has that many flags around it opens all its other neighbours at once. It is the single biggest difference between playing slowly and playing quickly, and it is also how a wrong flag gets punished immediately.
Three sizes and separate best times
9×9 with 10 mines is the size to learn the patterns on. 16×16 with 40 is where reading two numbers against each other starts to matter. 30×16 with 99 is the classic expert board, and it scrolls sideways on a phone rather than shrinking the squares below what a finger can hit.
Your best time is kept per size. The clock starts on your first click.
Generated here, kept here
Boards are generated on your device, one per game, and are never fetched from anywhere. Nothing is recorded but the best time per size, kept in this browser.
The page also needs nothing from the network once it has loaded, so installing it from the burrow turns it into an offline game.
Frequently asked questions
What does the number on a square mean?
How many of the eight squares touching it contain a mine. A 1 with only one unopened neighbour means that neighbour is the mine. Almost every deduction in the game is a longer version of that.
Do I have to flag every mine to win?
No. The game is won when every square that is not a mine has been opened. Flags are a note to yourself, and a way to use the click-a-number shortcut.
Is a guess ever unavoidable?
On the larger boards, occasionally yes — some late positions genuinely have two possibilities and no information to separate them. It is rarer than it feels; most apparent guesses have a deduction available somewhere else on the board.
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