How to Play Minesweeper

The rules

Open a cell and one of two things happens. If it hides a mine, the run ends. If it does not, it shows a number: how many of its eight neighbours — diagonals included — are mines. A cell with no neighbouring mines shows nothing and opens all of its neighbours automatically, which is the cascade that clears large areas in one click.

Your first click is always safe, and so is everything immediately around it. The board is generated in response to that click rather than before it, so there is no opening guess to get wrong.

Flag a cell to mark it as a mine you have worked out. Flags never affect the board — they are a note to yourself, and to anyone playing with you. You win when every safe cell is open; the flags do not have to be right, or there at all.

Chording, the shortcut worth learning

Press both mouse buttons together on an opened number. If you have already flagged as many neighbours as the number says, every other neighbour opens at once. A 3 with three flags around it clears its five remaining cells in one motion instead of five.

This is where nearly all of the difference between a slow time and a fast one lives. It is also the reason flags are worth placing even though the win condition ignores them: flags are what make chording possible.

Chording is only worth as much as your flags are right, which comes down to reading the patterns. The pattern drills are short interactive puzzles for exactly that — 1-1, 1-2, 1-2-1, 1-2-2-1, and the rule they are all special cases of.

Playing by keyboard

Arrow keys or WASD move a cursor, Space or Enter opens the cell under it, F flags it, and Escape hides the cursor again. The whole game is playable without a mouse.

The three modes

Co-op puts everyone in the room on a single shared board. You see each other's cursors live, and one person's mistake ends the round for the group — which is what makes talking to each other worth it. Everyone scores a point for each safe cell their own move opens, cascades included.

1v1 gives two players the same layout and starts them at the same moment. You are not sharing a board, you are racing identical ones, so it comes down purely to who reads the numbers faster.

The daily challenge is one board a day, the same for everyone, ranked by time, with a single attempt.

No-guess boards

Classic Minesweeper will eventually deal you a position where two cells are equally likely to be the mine and nothing on the board can tell them apart. Losing there is a coin flip, not a mistake. Every board here is built so that never happens: at every point in the game there is at least one cell you can prove is safe using only what the board is showing you. It does not mean the board is easy, and it does not mean you cannot lose — if you lose, you missed something, and the deduction was there.

It is generate-and-test. A candidate layout is drawn at random, and a solver plays it the way a careful person would — only ever taking moves it can prove, never guessing. If the solver clears the board, you get that layout. If it gets stuck, the candidate is thrown away and another is drawn, up to 300 times. The solver is the honest part: it is not checking that the board looks reasonable, it is checking that a complete chain of deductions exists from the opening cascade to the last safe cell.

Solvable layouts get rare fast as mine density climbs, and the rate was measured rather than guessed at. On a 20x16 board, the share of random candidates the solver can clear:

• 18.8% density — 17% of candidates are solvable
• 20.6% density — 7% of candidates are solvable
• 22% density — 3% of candidates are solvable
• 24% density — 0.3% of candidates are solvable

At 300 attempts, 20.6% never once fell through to an unchecked board across 200 games on every board size. 22% still did. So 20.6% is where the hardest difficulty sits — not because it felt right, but because it is the densest board the guarantee survives. It is also exactly classic Minesweeper's Expert density, 99 mines on a 30x16 grid.

Difficulty is a mine density rather than a fixed count, applied to whichever board size you pick, so the mine count is always derived from the two:

• Easy — 12.3%
• Medium — 15.6%
• Hard — 18.8%
• Extreme — 20.6%

The honest caveat: if all 300 candidates fail, the generator returns the first one it drew rather than failing outright — an unchecked board, indistinguishable from a real one while you are playing it. That is why the density ceiling exists. Custom boards can be built up to 32 by 16 with any mine count under half the grid; push the density past the presets and you are outside the measured range, where the guarantee is best-effort rather than reliable.

Common questions

Is Minesweeper a game of luck?

Not here. Every board is checked for logical solvability before you see it, so there is always a next move you can deduce. Classic Minesweeper can deal you an unavoidable 50/50 near the end; these boards cannot.

What does the number in a cell mean?

How many mines touch that cell, counting all eight neighbours including diagonals. A 1 has exactly one mine among its neighbours; a cell with no number has none at all, which is why opening one clears a whole region.

Can you play Minesweeper with friends?

Yes. Co-op puts everyone on one shared board with live cursors, and 1v1 gives two players the identical layout to race. Both take a room code, or quick match pairs you with whoever else is looking.

What is chording in Minesweeper?

Pressing both mouse buttons on an opened number whose mines you have all flagged opens every remaining neighbour at once. It is the single biggest speed gain available, and most players never learn it.

Do I need an account to play?

No. Rooms and the daily challenge both work with no sign-up and no download. An account only adds saved stats and streaks.

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