Sumknot is a crossword built out of equations.
The figure is irregular on purpose. Equations cross at shared cells, so a single number closes two of them at once - and has to be right twice. Slide the tiles into the frame until every line reads true.
One rule to know before you start: arithmetic here runs strictly left to right, with no operator precedence. 2 + 3 x 4 is 20, not 14. It is not a simplification of school arithmetic, it is a smaller rule, and it makes every line readable in one pass.
Every figure is generated and then proved by our own solver: exactly one solution, reachable by logic alone.
• DAILY - the same figure for everyone, once a day. Beat the clock, keep your streak, share your result without spoiling it.
• LEVELS - 150 figures in three chapters, from four-tile openers to knots that cross a dozen times.
• ENDLESS - a fresh figure whenever you want one, with a code you can send.
Made to respect your time:
• No lives, no forced timers, no forced videos.
• Gold, silver or bronze on every board, by how close you came to par.
• Three hints on every board.
• Colour-blind shapes, high contrast and a choice of palettes.
• Dark mode. Works offline. Tiny download.
• No sign-up and no accounts: progress stays on your device.
A quiet knot of numbers for a coffee break.
A crossword made of equations: one number closes two lines at once.