Doppit

The puzzle

Doppit's board is a connected grid partitioned into shaded regions. Each region carries a numeric constraint. A 5 means the cells in this region must sum to 5. An = means every cell must be equal. A ≠ means every cell must be different. <5 means the sum is less than 5; >5, more. A blank region accepts anything.

A tray of dominoes sits below the board. Drag each one onto the grid so every region's constraint is satisfied. The in-game solver verifies that every generated puzzle has exactly one solution before it's served.

Endless practice, plus a daily

Doppit started because of Pips. I loved it, but it's a daily-only puzzle. Solve today's and you wait 24 hours for another one. I wanted more right then, so I built Doppit to generate as many as I felt like playing.

Doppit makes a new puzzle every time you ask. No limit. Solve as many as you want, change difficulty whenever, and the solver guarantees each one has exactly one solution.

There's a daily puzzle on top of that, if you want a single set piece to come back to each day.

Three difficulties

Easy has small boards and single-deduction puzzles. Friendly to first-timers. Medium has larger boards with chained deductions; you'll have to think two or three steps ahead. Hard can take 10 minutes or more to solve. Are you up for it?

The name

"Doppit" combines doppio (Italian for "double") with the act of dropping a domino onto the board.

The look

The visual style is "The Domino Almanac." Letterpress buttons, paper grain with a vignette, tracked-caps eyebrows, pip-dot ornaments, and a wax-stamp seal on the celebration screen. The idea was to make a Sunday-newspaper puzzle column that happens to live on the web.

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