Opening the field
Your first square is always safe. Clicking near the middle tends to open a larger blank area than clicking a corner, which gives you more numbers to work from. Then work outward from the edge of the opened area, where the clues are.
The two basic deductions
Every number counts the mines among its eight neighbors. If a number already touches that many flags, all its other closed neighbors are safe. If its closed neighbors, counting flags, equal the number, all of them are mines. Most of the board falls to these two rules.
“Count it once and commit. Hesitation is the only thing slowing you down.”
Nova
Patterns worth memorizing
A few shapes appear along the boundary of nearly every board. Recognizing them on sight, without counting, saves the most time.
- 1-1 against a wall: two 1s side by side along an edge of the opened area share their mine in the first two cells, so the third cell beside the second 1 is safe.
- 1-2-1 in a row: the mines are under the two 1s, and the cell under the 2 is safe.
- 1-2-2-1 in a row: the mines are under the two 2s, and the cells under the 1s are safe.
- 1-2 along the boundary: when the 2 has exactly one closed cell that the 1 does not touch, that cell is a mine.
Flag only what you need
Flags help you keep track, but each one costs a click. Many fast players flag only the mines that unlock nearby safe squares. Whatever your habit, never flag a cell you are not certain of: a wrong flag makes the next deduction wrong too.
Use the mine count late in the game. When only a few mines are left, counting them against the closed cells often settles the last region.
When you have to guess
Minesweeper boards are generated, not hand-made, so now and then a region cannot be solved by logic. Before guessing, check every clue around it again and use the remaining mine count. If you still must guess, pick the cell that would reveal the most information if it is safe, usually one away from the boundary, not one squeezed between clues.