Rules & quick reference
| Beginner | 9 × 9; 10 mines |
|---|---|
| Intermediate | 16 × 16; 40 mines |
| Expert | 30 × 16; 99 mines |
| First reveal | First cell and its neighbors are mine-free; later guessing may be required |
Open a safe starting area
Choose a difficulty and reveal any unopened cell. Mines are placed only after that first reveal, excluding both the selected cell and every neighbor. The opening therefore has zero adjacent mines and expands into a clear area. The timer starts on that reveal. This protection applies to the first opening only. Later positions may require assumptions or guesses; the generator does not claim to produce exclusively no-guess boards.
Read numbers and mark hypotheses
A number counts mines in the eight surrounding positions, including diagonals. Right-click an unopened cell to toggle a flag. On a touch device, enable Flag mode before selecting cells you want to mark, then turn it off to reveal again. Flags are hypotheses and the game does not check them for you. The number of placed flags is shown against the difficulty’s mine count, and flags cannot exceed that count. A flagged cell is protected from an ordinary reveal until unflagged.
Use chording only when flags are justified
Select an already opened numbered cell when the number of neighboring flags equals its number. This chord opens all other unopened neighbors at once. If a flag is wrong, the count can still match while an unflagged mine remains, and the chord will lose the game. Chording is a shortcut for applying an existing deduction; it is not a correctness check. Empty areas expand automatically with a flood fill so you do not have to reveal every zero individually.
Complete and compare a board
You win by opening every non-mine cell; flagging every mine is not required. A mine hit ends the run and reveals mine positions. A completed win records the elapsed time in a history specific to that difficulty. Expert boards scroll horizontally on a narrow screen rather than shrinking every cell below a usable size. Random layouts differ in complexity, so a faster single board is not a precise measurement of improved skill. Compare several sessions and keep input method consistent.
Your result stays on this device
Completed game results are saved in this browser when local storage is available. Bests and recent history describe this device’s saved runs, not a public leaderboard. Changing browsers, clearing site data or using private browsing can remove them. Copy score writes only the visible result summary to your clipboard when you request it; sharing is your choice. Clear local game data removes scores, daily completion markers and the saved 2048 board for this origin. No game result is uploaded, and the games remain usable when persistent storage is unavailable. Use the rule table to check what the active mode measures before comparing another session. A changed duration, input method or grid difficulty can change the task even when the displayed score uses the same unit.
Frequently asked questions
Is the first click always safe?
Yes. Mines exclude the first revealed cell and its neighbors, producing a zero opening.
Are all boards solvable without guessing?
No. Safe first opening does not imply a no-guess board.
How do flags work on mobile?
Enable Flag mode, tap cells to mark them, then disable Flag mode to reveal.
Why did a chord hit a mine?
A matching flag count is not proof that those flags are correct. Wrong flags can leave a mine exposed.
Built by Mihai · Reviewed 2026-10-24 · Read the related technical guide · Testing policy