Four puzzles, zero accounts, pure logic
Cross-sums, inequalities, skyscrapers, and arithmetic cages. Four grids generated fresh every game, checked before they appear, and one shared challenge every day. Nothing to install, nothing to sign up for.
Four games, one challenge a day, the same for everyone
Each game draws its daily grid from the date. No server is contacted: the same date gives the same seed, and therefore the same grid, on any device. Solve one and your streak moves forward by a day.
Complete a challenge today to start a streak.
Four games, four ways to rack your brain
Each has its own page, its own illustrated rules, and its own best scores. None depends on another.
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Cross-sums
Kakuro
Fill the white cells with 1 to 9 so that each block reaches its sum, never repeating a digit within the same block. A few cells are already filled in.
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Grid and inequalities
Futoshiki
Place 1 to N once per row and column while respecting the chevrons: the point of the sign always aims at the smaller number.
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Heights and lines of sight
Skyscrapers
Place towers of different heights so that each edge sees the right number of skyscrapers, with taller ones hiding shorter ones.
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Latin square and arithmetic
Calcudoku
Fill the grid with no repeats in any row or column, and make each cage match its result and its operation.
Three clicks, no more
- Pick a game. Each game has its own address. You can bookmark it and land directly on the board.
- Play. Everything runs in your browser. The site calls no server during a game, because there is no server to call.
- Keep your best scores, or don't. If you accept the “Preferences” category, your best times and your streak stay in this browser. Otherwise, the page starts from scratch on every visit.
A few verifiable facts
Verified grids
Every Kakuro, Futoshiki, Skyscrapers, and Calcudoku grid is generated and then run through a solver that confirms a unique solution. Nothing unsolvable, nothing ambiguous, nothing that requires guessing.
No third-party requests
No remote fonts, no analytics script, no share buttons. Open your browser's network tab: after the page loads, nothing else happens.
Nothing depends on color
Digits, chevrons, sums, cages, and heights all read in black on parchment. Color highlights; it never carries the information on its own.
A single script file
The whole site, games and solvers included, fits in one stylesheet and one JavaScript file. No framework, no build step.
What we get asked most
No. No account, no email address, no password. You open the page and you play. Your best scores stay in your browser, and only if you have accepted the “Preferences” category.
Nothing, and nothing later either. There is no paid version, no tokens to buy, and no game is locked behind a paywall.
No. The site loads no analytics script and no ad network, and it sends no requests to any third-party server. All four games run entirely in the tab you opened.
Yes, and exactly one. Every grid — Kakuro, Futoshiki, Skyscrapers, Calcudoku — is generated and then checked by a solver before it appears. Guessing is never required.
Each game draws a grid from today's date. It is the same for everyone, it changes at midnight, and solving any one of the four moves your streak forward by a day. Nothing is sent anywhere: the date alone is enough to rebuild the same grid.
Yes. The layout is mobile-first, and every grid offers large touch targets with a number pad below the board.
Futoshiki if you like sudoku. Skyscrapers for a visual challenge. Calcudoku if you enjoy mental math. Kakuro for fans of sums.