Most people play Minesweeper by clicking squares and hoping. That's not a strategy — that's gambling. The actual game is a logic puzzle, and most boards can be solved without guessing at all.
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How Minesweeper Works
Every numbered cell tells you exactly how many mines are hidden in the 8 surrounding squares. A 1 means one of its neighbours is a mine. A 3 means three of them are.
Your job is to use those numbers as constraints to deduce which squares are safe and which are mines — without clicking a mine.
The first click is always safe. The board generates after your first click to guarantee you don't immediately lose.
The Core Rules (Logic, Not Luck)
Rule 1 — Flag Forced Mines
If a numbered cell has exactly as many unrevealed neighbours as its number, every one of those neighbours is a mine. Flag them all.
Example:
A cell showing 3 has exactly 3 unrevealed neighbours → all 3 are mines → flag all 3
This is the most common deduction. Apply it constantly as you reveal more of the board.
Rule 2 — Clear Forced Safe Squares
If a numbered cell already has as many flags as its number, all remaining unrevealed neighbours are safe to click.
Example:
A cell showing 2 has 2 flagged neighbours → any other unrevealed neighbours are 100% safe → click them
Combine Rule 1 and Rule 2 repeatedly and you'll solve most of the board through pure logic.
Rule 3 — The Subtraction Technique
This is where it gets interesting. When two numbered cells share unrevealed neighbours, you can subtract their constraints to deduce new information.
Example:
Cell A shows 1, with neighbours: [X] [Y]
Cell B shows 1, with neighbours: [X] [Z]
Both share square X. If A=1 and B=1, and they share X:
→ Either X is the mine for both, or X is safe and both [Y] and [Z] are mines.
→ Since B only has 1 mine and shares X with A: if X is not the mine, then Z must be.
→ This means Y and Z have the same mine status as each other.
This sounds complex but becomes intuitive with practice. Look for pairs of cells where one is a subset of the other — the difference between them is always a forced mine or safe square.
Opening Strategy — Where to Start
Click corners and edges first. Corner squares have only 3 neighbours (vs 8 for interior squares), so any number revealed in a corner is easier to satisfy and opens more deductions faster.
Click the centre on large boards. On Expert (30×16), a centre click often opens a large safe area, giving you more numbers to work with from the start.
Avoid clicking isolated squares until you have surrounding context. An isolated revealed square gives you less information than one adjacent to already-revealed numbers.
Flagging Strategy
Only flag when you're certain. Some players flag aggressively to track possibilities. This backfires — wrong flags block Rule 2 deductions and force you to recheck your own work.
Use question marks for uncertain squares (right-click twice on most implementations). This marks a square as "possibly a mine" without committing to it, keeping your flag count accurate.
Count your flags. The mine counter at the top shows remaining unflagged mines. If it reaches zero and you still have unrevealed squares, those squares are all safe.
When You Have to Guess
On some boards — particularly in corners on Expert difficulty — you will reach a position where two or more squares are equally likely to be mines with no logical deduction possible. This is a genuine 50/50 and requires a guess.
When forced to guess:
- Calculate which square has the lowest mine probability based on nearby numbers
- Pick corners over edges — a corner guess that's wrong ends the game, but corner squares are statistically less likely to be mines in many configurations
- Accept that Expert Minesweeper has an irreducible ~20% guess rate even with perfect play — the goal is to minimise guesses, not eliminate them entirely
Difficulty Reference
| Difficulty | Grid | Mines | Mine density |
|---|---|---|---|
| Beginner | 9×9 | 10 | ~12% |
| Intermediate | 16×16 | 40 | ~16% |
| Expert | 30×16 | 99 | ~21% |
Higher mine density = more guesses required. Beginner and Intermediate can often be solved without any guessing with good technique.
Practice
The fastest way to improve is repetition on Intermediate difficulty — big enough to practice the subtraction technique, small enough to complete in under 5 minutes.
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