Play Minesweeper without installing anything

The job

Minesweeper is pure deduction: each number counts mines in the eight surrounding cells, flags mark where you think they are, and clearing everything else wins.

Start a board

Pick easy (9×9, 10 mines), medium (16×16, 40), or hard (16×30, 99). Mines are placed after your first click — and never on it or its neighbours — so the opening always reveals an area.

• Right-click flags a cell; on touch, turn on flag mode and tap instead.
• A revealed 0 opens its whole neighbourhood — that's the cascade that solves boards fast.

Worked example

A cell showing 1 with only one closed neighbour means that neighbour is the mine — flag it. A 2 between two flagged cells means every other neighbour is safe to click.

Scope

Classic rules, no timer pressure added — the counter shows mines left, not seconds. Boards stay in the tab; refresh starts a new game.