# Logic Puzzles CA

> Free online logic puzzles and brain games — 30+ hand-crafted puzzle types including Sudoku, Nonograms, KenKen, Minesweeper, and Crowns. Every puzzle has a unique solution reachable by pure deduction (no guessing). Playable instantly in any browser with no account, no download, and no paywall. Printable versions and iOS/Android apps are available for several puzzles.

Each game page below explains the rules, solving strategies, common mistakes, history, and FAQ for that puzzle type, and lets you play it directly in the browser.

## Games

- [Aquarium](https://logicpuzzles.ca/games/aquarium): Water-filling logic puzzle where gravity constrains every deduction.
- [Battleships](https://logicpuzzles.ca/games/battleships): Solitaire Battleships puzzles online for free
- [Binary Sudoku+](https://logicpuzzles.ca/games/binary-sudoku-plus): Fill grids with 0s and 1s under row/column balance constraints.
- [Block Merge](https://logicpuzzles.ca/games/block-merge): Block Merge online for free
- [Butterfly Mahjong](https://logicpuzzles.ca/games/butterfly-mahjong): Butterfly Mahjong online for free
- [Color Flood](https://logicpuzzles.ca/games/palette-path): Connect matching colors while filling the entire board.
- [Color Links](https://logicpuzzles.ca/games/color-links): Color Links (Numberlink) online for free
- [Crowns](https://logicpuzzles.ca/games/crowns): Symmetry-based N-Queens-style grid puzzle solved with pure deduction.
- [Cryptograms](https://logicpuzzles.ca/games/cryptograms): Cryptograms online for free
- [Daily Logic Puzzles](https://logicpuzzles.ca/games/daily-logic-puzzles): A fresh set of bite-sized logic challenges every day.
- [Dominosa](https://logicpuzzles.ca/games/dominosa): Dominosa puzzles online for free
- [Dot Stream](https://logicpuzzles.ca/games/dot-stream): Path-finding puzzles based on connecting dots through the grid.
- [Enclose Fox](https://logicpuzzles.ca/games/enclose-fox): Daily pen-building puzzle: enclose the fox with limited walls.
- [Euchre](https://logicpuzzles.ca/games/euchre): Euchre online for free
- [Final Phrase](https://logicpuzzles.ca/games/final-phrase): Final Phrase online for free
- [Futoshiki](https://logicpuzzles.ca/games/futoshiki): Futoshiki puzzles online for free
- [Galaxies](https://logicpuzzles.ca/games/galaxies): Galaxies (Tentai Show) puzzles online for free
- [KenKen](https://logicpuzzles.ca/games/kenken): Arithmetic-cage logic puzzle blending Sudoku placement with math.
- [Kurodoku](https://logicpuzzles.ca/games/kurodoku): Kurodoku puzzles online for free
- [Light Up](https://logicpuzzles.ca/games/light-up): Light Up (Akari) puzzles online for free
- [LITS](https://logicpuzzles.ca/games/lits): LITS puzzles online for free
- [Logic Grid Puzzles](https://logicpuzzles.ca/games/logic-grid-puzzles): Logic Grid Puzzles online for free
- [Medieval Word Twister](https://logicpuzzles.ca/games/medieval-word-twister): Medieval Word Twister online for free
- [Minesweeper](https://logicpuzzles.ca/games/minesweeper): Minesweeper online for free
- [Mosaic](https://logicpuzzles.ca/games/mosaic): Mosaic (Fill-a-Pix) puzzles online for free
- [Nonograms](https://logicpuzzles.ca/games/nonograms): Picture logic puzzles (Picross/Griddlers) solved from number clues.
- [NoriNori](https://logicpuzzles.ca/games/norinori): NoriNori puzzles online for free
- [Number Merge](https://logicpuzzles.ca/games/number-merge): Number Merge online for free
- [Nurikabe](https://logicpuzzles.ca/games/nurikabe): Nurikabe puzzles online for free
- [Pipes](https://logicpuzzles.ca/games/pipes): Pipes (Plumber) puzzles online for free
- [Renzoku](https://logicpuzzles.ca/games/renzoku): Renzoku puzzles online for free
- [Skyscrapers](https://logicpuzzles.ca/games/skyscrapers): Skyscrapers puzzles online for free
- [Slant](https://logicpuzzles.ca/games/slant): Slant (Gokigen Naname) puzzles online for free
- [Slider Puzzle](https://logicpuzzles.ca/games/slider-puzzle): Slider Puzzle online for free
- [Slime Sweeper](https://logicpuzzles.ca/games/slime-sweeper): Slime Sweeper online for free
- [Solitaire Pro Collection](https://logicpuzzles.ca/games/solitaire-pro-collection): Klondike, FreeCell, Spider, TriPeaks, Pyramid, and Golf solitaire.
- [Sudoku](https://logicpuzzles.ca/games/sudoku): Sudoku online for free
- [Tents & Trees](https://logicpuzzles.ca/games/tents-and-trees): Tents & Trees puzzles online for free
- [Thermometers](https://logicpuzzles.ca/games/thermometers): Thermometer puzzles online for free
- [Word Ladder](https://logicpuzzles.ca/games/word-ladder): Word Ladder puzzles online for free
- [Word Wheel](https://logicpuzzles.ca/games/word-wheel): Word Wheel online for free
- [Yin-Yang](https://logicpuzzles.ca/games/yin-yang): Yin-Yang puzzles online for free

## Browse

- [All Logic Games](https://logicpuzzles.ca/logic-games): The full collection of grid-based deduction puzzles
- [Word Games](https://logicpuzzles.ca/word-games): Word Wheel, Word Ladder, and other vocabulary puzzles
- [Card Games](https://logicpuzzles.ca/card-games): Solitaire variants and Euchre
- [Printable Puzzles](https://logicpuzzles.ca/printable/sudoku): Downloadable PDF puzzles (Sudoku, Crowns, Nonograms, KenKen, Aquarium, Tents & Trees, Binary Sudoku+)
- [Mobile Apps](https://logicpuzzles.ca/apps): iOS and Android versions of our puzzles
- [FAQ](https://logicpuzzles.ca/faq): Rules, devices, accounts, and puzzle-design questions
- [About](https://logicpuzzles.ca/about): Who builds these puzzles and why

## Recent Blog Posts

- [The Solver's Dozen: Twelve Evidence-Backed Rules for Better Puzzling](https://logicpuzzles.ca/blog/the-solvers-dozen): A season of essays on the science, math, and history of solving, distilled to one page: twelve rules with receipts — from pigeonhole counting to walking away on purpose — that make any grid, and most problems, yield sooner.
- [The Brainteaser Interview: What Hiring Got Wrong About Puzzles](https://logicpuzzles.ca/blog/the-brainteaser-interview-what-hiring-got-wrong-about-puzzles): For twenty years, tech companies hired people by asking why manhole covers are round. Then Google checked the data and called it "a complete waste of time." A puzzle site's honest take on what puzzles can and cannot tell you about a mind.
- [Dominosa and the Broken Chessboard](https://logicpuzzles.ca/blog/dominosa-and-the-broken-chessboard): Cut two corners off a chessboard and no arrangement of 31 dominoes will ever cover it — provable in two sentences, unbelievable until you see it. The coloring trick behind that classic powers domino puzzles, physics, and the art of proving "never."
- [God's Number Is 20: What the Rubik's Cube Taught Mathematics](https://logicpuzzles.ca/blog/gods-number-is-20): Any scramble of the 43-quintillion-position cube can be solved in 20 moves — never more. Proving it took thirty years, borrowed supercomputers, and a question named after God. The gap between 20 and how humans actually solve is the interesting part.
- [Why Explaining a Puzzle Out Loud Solves It](https://logicpuzzles.ca/blog/why-explaining-a-puzzle-out-loud-solves-it): Programmers confess their bugs to rubber ducks and the bugs surrender. Psychology has been documenting the trick since 1989 — plus the strange case where saying it out loud makes you worse.
- [Galaxies: The Puzzle Where Every Move Happens Twice](https://logicpuzzles.ca/blog/galaxies-solving-by-symmetry): Nikoli's "Tentai Show" is a bilingual pun — astral show, point symmetry — and a puzzle where each deduction instantly buys its mirror twin. On solving with symmetry, and why physics is played the same way.
- [The Ostomachion: Archimedes and the Oldest Puzzle We Know](https://logicpuzzles.ca/blog/the-ostomachion-archimedes-and-the-oldest-puzzle): A prayer book sold at auction for two million dollars turned out to hide Archimedes' lost notebooks — including a 14-piece puzzle that may be the birth certificate of combinatorics. Its solution count took until 2003 to find: 17,152.
- [Futoshiki and the Arrow of Inequality](https://logicpuzzles.ca/blog/futoshiki-and-the-arrow-of-inequality): Futoshiki means "inequality," and its little arrows never tell you what a cell is — only what it's bigger than. A guide to solving with chains, ceilings, and floors, and the branch of math that lives between the cells.
- [Desirable Difficulties: Why Comfortable Practice Makes Weak Solvers](https://logicpuzzles.ca/blog/desirable-difficulties): Fifty years of learning research converges on an uncomfortable law: the practice that feels most productive teaches the least. What testing, mixing, and struggling actually do — and how to aim your puzzle habit at growth.
- [The Crossword Contest That Recruited Codebreakers](https://logicpuzzles.ca/blog/the-crossword-that-recruited-codebreakers): In 1942, a newspaper ran a puzzle speed contest — and the War Office quietly hired the winners. On Bletchley Park, the D-Day crossword panic, and why puzzle minds have always been weapons-grade.
- [Twenty Questions with Claude Shannon: How Much Is a Clue Worth?](https://logicpuzzles.ca/blog/twenty-questions-with-claude-shannon): In 1948 an engineer who juggled on unicycles invented a unit for information itself. His "bit" explains why twenty questions can find one thing in a million, why cryptograms are crackable, and what a good puzzle clue actually does.
- [How a Computer Solves Sudoku (and Why It Does It Backwards)](https://logicpuzzles.ca/blog/how-a-computer-solves-sudoku): Your solver of choice cracks any Sudoku in milliseconds — but not the way you do. Inside constraint propagation, Knuth's dancing links, and the strange fact that the machine's hardest puzzle isn't yours.
- [Nurikabe: The Wall That Builds Itself](https://logicpuzzles.ca/blog/nurikabe-the-wall-that-builds-itself): Named for a ghost that blocks travelers on dark roads, Nurikabe asks you to flood a grid with one connected sea around numbered islands. Its secret: connectivity is a clue — some cells are black simply because nothing could ever reach them.
- [The Pigeonhole Principle: The Simplest Idea That Keeps Winning](https://logicpuzzles.ca/blog/the-pigeonhole-principle): Ten pigeons, nine holes — some hole holds two. From this one observation: why two Londoners share an exact hair count, why no compressor shrinks everything, and why your best Sudoku moves were pigeonhole arguments all along.
- [KenKen: The Classroom Invention That Teaches Without Teaching](https://logicpuzzles.ca/blog/kenken-the-classroom-invention-that-teaches-without-teaching): A Tokyo cram-school teacher who refused to lecture invented a puzzle instead — "cleverness squared" — and it spread from his classroom to newspapers worldwide. The story, the philosophy, and the arithmetic that cracks it open.

## Optional

- [Full sitemap](https://logicpuzzles.ca/sitemap.xml)
- [Press kit](https://logicpuzzles.ca/press)
- [Contact](https://logicpuzzles.ca/contact)