Sudoku Made and maintained by Brian Hamilton and Karan Hamilton.
Brian builds the playable puzzle tools, while Karan helps test clarity, difficulty feel, and the player experience.
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Summer Sudoku: The "I'm Bored" Board
Summer Sudoku takes classic Sudoku to the beach with nine tiles — sun, sunglasses, beach umbrella, ice cream, watermelon, palm tree, ocean wave, seashell, and cold drink. Icons, digits, or a mix of the two; each tile claims exactly one spot in every row, column, and box.
Built for the long holidays
Every family knows the schedule: six weeks of freedom, and the first "I'm bored" lands before the end of week one. This board is for the flat stretches of summer — the back seat of a long drive, the airport gate, the hour after lunch when it is too hot to be outside anyway. A 4x4 needs a couple of minutes, a 6x6 outlasts most queues, and nothing needs packing, charging separately, or picking up off the floor of the car.
You don't reach the sea until 9x9
The set is arranged like the trip itself. The 4x4 board is the packing list — sun, sunglasses, beach umbrella, ice cream. At 6x6 you have clearly arrived somewhere: the watermelon is cut and there is a palm tree. But the ocean wave, the seashell, and the cold drink only appear on the full 9x9, so the beach itself has to be earned the hard way. We find this fair.
For young solvers: start a 4x4 Easy at the same time as an actual ice cream. The puzzle should win. Rematches are traditional.
The one real hazard is the sun
For once, the tiles are not the problem — a wave looks nothing like a watermelon, and this is one of the most instantly readable sets we have. The genuine difficulty of summer solving is glare. If you are playing outside, the plain Numbers view is the highest-contrast option and the easiest to read in direct light; save the full beach scenery for the shade it deserves.
No repeats, even on holiday
Every puzzle has a single solution, and no tile appears twice in any row, column, or box — the rule does not take August off. How difficulty works and what auto notes do is packed into the Themed Sudoku page, alongside the rest of the collection for the journey home.
Summer Sudoku FAQ
In order of arrival: the 4x4 board uses the sun, sunglasses, beach umbrella, and ice cream; the watermelon and palm tree join at 6x6; and the ocean wave, seashell, and cold drink only appear on the full 9x9.
Bright sunlight flattens most screens, so the plain Numbers view — the highest-contrast display — is easiest to read in direct light, with brightness turned up. The picture tiles come into their own back in the shade.
That is mostly what it is for. A 4x4 fits a short wait, a 6x6 outlasts a boarding queue, and the whole thing lives on the phone that was coming with you anyway — nothing to pack and nothing to drop between the seats.