Minesweeper Game with 20 Levels, No-Guess Boards & Hints

Minesweeper is a logic puzzle: numbers tell you how many mines touch a cell, and you clear the field using deduction alone. This version is a complete game rather than a demo. It has 20 levels in four tiers, a Daily Board with a streak, boards that can always be solved without guessing, hints that explain the deduction in words, chording, extra lives on the easier levels, stars and best times. It is plain HTML, CSS and JavaScript with no libraries, images or audio files.

Boards that never force a guess

The classic frustration in Minesweeper is a 50/50 guess at the end of a long game. generateBoard() removes it. It picks a start cell, places the mines away from that cell and its neighbours, and then runs the logic solver on the finished board. Only boards that the solver can clear completely from the opening are kept, otherwise another seed is tried. The opening is revealed when the level starts, so a first-click guess is not needed either. A seeded random generator (mulberry32) means a level is the same board for every player.

The solver is the hint system too

findSteps() applies two rules to every revealed number. If a number already has all its mines marked, its other hidden neighbours are safe. If it has exactly as many hidden neighbours as mines left, they are all mines. When neither applies, the subset rule compares two numbers: if the hidden neighbours of one number are all neighbours of another, subtracting them settles the difference. The Hint button runs the same function on your current board and explains the result in words, for example "Every hidden cell next to the 1 at C3 is also next to the 2 at D3, and they need the same number of mines, so E3 is safe." It highlights the clue numbers in amber and the target cell in green (safe) or red (mine). If you have placed a wrong flag, the hint points that out first.

Controls for mouse, keyboard and touch

Left-click reveals, right-click flags, and clicking a revealed number does a chord: if the number of flags around it matches, every other neighbour is revealed at once, which is the fastest way to play. A press-and-hold flags on a touch screen, and a Flag mode button is there too. The keyboard works as well: arrow keys move a cursor, Space or Enter reveals, F flags, C chords, H hints and R restarts.

Lives, stars and the daily board

The first levels give three lives and later ones two or one: stepping on a mine costs a life, marks that mine and lets you carry on. Winning earns one star, a second star for a clean run with no mines hit and no hints, and a third for finishing under the par time. Clearing a level unlocks the next, and best times are saved. The Daily Board is a seeded 16 by 16 board with 40 mines, the same for everyone, and clearing it on consecutive days builds a streak.

Feel and scaling

Flood fills ripple outwards from the clicked cell, explosions shake the panel and flash the cell, a wave sweeps across the board when you win, and the sounds (clicks, flags, an explosion made of filtered noise and a win jingle) come from a Web Audio synth. Flags and mines are drawn as inline SVG, so they look the same everywhere. Progress, best times and the streak are saved to localStorage inside try/catch, and the whole game scales to short preview areas, from an 8 by 8 board up to 26 by 15.