Some puzzle games test your reflexes. These six test your reading: every cell, clue and card is information, and the win goes to whoever interprets it best. All six are free in your browser with no download and no account — open a tab and start deducing.
If you want a ranked list instead, read our best browser puzzle games. If you want technique, read the 10 puzzle tips. If you cannot decide, try the picker. This guide covers one family only: pure logic, where nothing is hidden except the answer.
1. Minesweeper: deduce every mine
Play now: Minesweeper
Three boards: beginner 9×9 with 10 mines, intermediate 16×16 with 40, expert 30×16 with 99. Your first click is always safe — mines are placed after it, never on your cell. A number tells you exactly how many mines touch that square; flag suspects with right-click and clear groups fast with chord-click on a satisfied number. You win by revealing every safe cell; one mine ends the run. Wins score up to 1,000 points minus 2 per second, so speed matters once logic is clean.
Tip: never guess while an unsolved number still has unmarked neighbors. Most lost runs come from one impatient click, not from forced 50/50s.
2. Sudoku Classic: nine digits, zero luck
Play now: Sudoku Classic
A fixed 9×9 grid across three difficulties. Fill every empty cell so each row, column and 3×3 box holds digits 1–9 exactly once; pre-filled cells are locked. Three mistakes end the run, so each entry is a commitment. Correct cells score 8 points plus a streak bonus up to +24, and clearing a level adds a time bonus plus 120 + 15 per level. Erasing breaks your streak, so pencil-mark mentally before committing.
Tip: finish the digit that is closest to complete first. Each placement removes candidates everywhere and the board starts solving itself.
3. Kakuro Master: sums with no repeats
Play now: Kakuro Master
Crosswords with arithmetic: fill white cells with digits 1–9 so each run matches its clue sum with no repeated digit inside the run. Boards grow with difficulty — 6×6, 8×8, 10×10 — and three mistakes end the run. Each correct cell scores 10 × difficulty multiplier (1/2/3), with a time bonus reduced by every hint used. The H key reveals a random empty cell when you are truly stuck, but it costs you.
Tip: learn the locked sums first: 16 in two cells is always 7+9, 17 is always 8+9. Free cells without possibilities are how experts start.
4. Mastermind: crack the 4-peg code
Play now: Mastermind
The computer hides a 4-peg code and you break it: black means right color in the right slot, white means right color in the wrong slot. Difficulty sets the palette and the ammunition — 6 colors/12 guesses, 7 colors/10 guesses, 8 colors/8 guesses — and repeats are allowed, so never rule out doubles. Wins score from a base of 200/400/700 minus 20 per extra guess, floored at 50.
Tip: open with four different colors. Information about which colors exist beats an early lucky hit almost every time.
5. Lights Out: toggle the grid dark
Play now: Lights Out
Every tap flips a cell plus its orthogonal neighbors on 4×4, 5×5 or 6×6 boards. Clear the whole grid to advance a level — but each level has a move budget (22, 26 and 30 moves at level 1), and running out ends the run. Scoring rewards fewer moves and faster solves from a base that grows per level. Chained levels keep the pressure rising.
Tip: solve in rows from the top: decide each cell solely to turn off the cell above it, and the last row resolves itself or tells you to restart early.
6. FreeCell: all 52 cards visible
Play now: FreeCell
The fairest solitaire: all cards face up across 8 columns, with 4 free cells as temporary parking and 4 home piles built by suit from Ace to King. Tableau builds downward alternating colors, any card can move to an empty column, and the stack you may move at once is limited by free space: (empty cells + 1) × 2^empty columns. Every card sent home scores +10, a full clear adds +500, and a 50-step undo plus auto-finish keep deep plans safe.
Tip: keep at least one free cell empty as your escape hatch. A full parking lot turns a solvable deal into a traffic jam.
Which board matches your mood
- Three minutes: Mastermind on easy or Lights Out level 1. One idea, one result.
- Ten focused minutes: Minesweeper intermediate or Kakuro medium. Deduction with a timer.
- A long session: Sudoku hard or a stubborn FreeCell deal. Deep reading, real payoff.
- Improving: stay one difficulty below your limit until wins feel routine, then climb. Close losses teach; blowouts do not.
Browse every option in the puzzle games hub.
Frequently asked questions
Are these games really free? Do I need to download anything? Yes, all six are completely free with no download and no registration, on PC, tablet and phone browsers.
Which one should a beginner start with? Mastermind on easy: 6 colors, 12 guesses, and every guess teaches you something even when it misses.
Which game is pure logic with no randomness? Sudoku, Kakuro and Lights Out: the whole board is visible from the start, so every loss is a reading error you can fix.
Are the rules here the real ones? Yes — board sizes, mine counts, mistake limits, scoring and controls are taken from each game's actual code, not from generic descriptions.
Can I play on my phone? Yes. Tap, keypad and swipe controls work the same as mouse and keyboard on every board.
Where do I go after these six? The best puzzle picks add more boards, and the 10 puzzle tips sharpen technique for all of them.