Intermediate Minesweeper

About Intermediate Minesweeper

Intermediate minesweeper is played on a 16×16 field with 40 mines. The mine density is similar to expert, but the smaller board makes it the best place to practise patterns like 1-2-1 and chording.

Minesweeper is a logic puzzle played on a grid of hidden cells, some of which hide mines. Every cell you uncover either shows how many mines touch it or, if none do, opens up the area around it. Use the numbers to work out where the mines are, flag them, and uncover every safe cell to win. Almost every move can be reasoned out, and the best players clear the expert board in well under a minute.

Also called: mines, mine sweeper.

How to play Minesweeper

1. Click or tap any cell to start. The first click is always safe and always opens an area, and the timer starts with it.
2. A revealed number tells you how many of the eight cells around it hold a mine. A blank cell has no mines around it, so its neighbours open automatically.
3. When you are sure a cell hides a mine, flag it: right-click, long-press on a phone, or switch the toolbar to Flag mode and tap.
4. Once a number has as many flags around it as its value, click the number (or middle-click it) to open all its other neighbours at once. This is called chording.
5. Uncover every cell that is not a mine to win. You do not need to flag the mines; the game flags them for you when you finish.
6. On a keyboard, the arrow keys move a cursor, Space or Enter reveals, and F places or removes a flag.

Rules

• Beginner is 9×9 with 10 mines, intermediate 16×16 with 40, and expert 30×16 with 99.
• Your first click, and the eight cells around it, never hold a mine.
• Neighbours include diagonals, so a cell in the middle of the board has eight, an edge cell five and a corner cell three.
• Chording only works when the flags around a number match it. If one of those flags is wrong, chording opens a mine and you lose.
• The mine counter shows the number of mines minus the flags you have placed. It can go below zero if you place too many flags.
• Uncovering a mine ends the game. All the mines are then shown, and any flag on a safe cell is crossed out.
• Your time is kept to the hundredth of a second, and the best winning time for each level is saved in your browser.
• The board is saved after every move, so you can close the tab and carry on later. The clock pauses while you are away and restarts on your next click.

Minesweeper tips and strategy

• Start from the edges of the opening. Numbers next to lots of revealed cells have few hidden neighbours, so they are the easiest to solve.
• A 1 touching only one hidden cell means that cell is a mine. Likewise, a 3 in a corner of the revealed area with exactly three hidden neighbours means all three are mines.
• A satisfied number frees its neighbours. If a 2 already has two flags around it, every other cell touching it is safe: chord it.
• 1-2-1 along a wall: the mines are under the two 1s and the cell under the 2 is safe. Look for this pattern in any straight line of revealed numbers.
• 1-2-2-1 along a wall: the mines are under the two 2s, and the cells under both 1s are safe.
• 1-1 at a wall: when a line of numbers starts with 1-1 against a wall or the board edge, the first 1 touches two hidden cells and the second 1 touches those two plus one more. That third cell is safe. The same idea works for any pair: compare the cells two numbers share, and the difference tells you what is left over.
• Corners and edges have fewer neighbours, so the numbers there give tighter information. A 1 in the corner of an opening often resolves immediately.
• Use the mine counter at the end. When only a few hidden cells are left, the number of mines remaining can settle a spot that the numbers alone cannot.
• If you must guess, guess where it tells you the most. Corners have only three neighbours, so they are the likeliest cells to be blank and open a new area.
• For speed, flag only where it helps you chord. Many fast players barely flag at all and simply avoid the mines.