Calculation

A thinking solitaire. The four foundations start at A, 2, 3 and 4 and go up by 1, by 2, by 3 and by 4 (after K you wrap round: Q + 2 = A), regardless of suit; all of them end on K. Draw cards from the stock one at a time: each one goes to a foundation or to one of the four waste piles below. Only the top card of a waste pile can be played, so spread them wisely. The stock cannot be turned over. Tap a card and it goes to the best place, or drag it. 💡 gives a hint and ↩️ undoes.

Yes. It is free, with no ads or purchases, and you do not need to sign up or download anything: it runs in your browser.

It needs a connection to load; once open, the game keeps running even if the connection drops.

Yes, on Android TV, Google TV or Fire TV. D-pad to a card · OK moves it. Up to 4 people can play taking turns.

It recreates the mechanics of Calculation · Broken Intervals, with emoji graphics, up to 120 levels with easy, normal and hard modes and touch controls.