Keisan
Fill the grid so no digit repeats in a row or column, and every cage reaches its target with its operation.
Today's puzzle
6×6, Steady. The same board as Numeriqo's daily, for everyone.
A new puzzle
The rules
- Fill the grid with 1 up to its size; no digit repeats in a row or column.
- The digits in each outlined cage combine to the number in its corner, using the sign beside it.
- − and ÷ cages have two cells, in either order. A digit may repeat inside a cage if the two cells share no row or column.
Tap a cell, then a digit. Notes pencils in the digits a cell could still take. With a keyboard: arrow keys move, digits enter, Shift with a digit makes a note, Backspace clears.
The techniques
The solver that builds each puzzle knows 16 named techniques, listed here in the order it reaches for them. A puzzle is kept only if they are enough to finish it.
- Free Cells
- Factors
- High & Low
- Difference & Quotient
- Cage Combinations
- Last Candidate
- Only Place
- Last Cell
- Matching Sets
- Hidden Sets
- Cage Points
- Line Claims
- Rule of N
- Spill Over
- Odd & Even
- X-Wing
Questions
Do I ever have to guess in Keisan?
No. Every puzzle is proved to have exactly one solution before it reaches you, and each step can be reasoned out.
Is Keisan free to play here?
Yes. Today's 6×6 puzzle and new 3×3 to 5×5 grids at every difficulty are free, with no account and no ads. Grids up to 9×9, the lessons and the hints are in Numeriqo, the app.
Is today's puzzle the same as in the app?
Yes. The daily puzzle is made from the date, so this site and the app serve the same one.
Along the street
In Numeriqo
Keisan is the puzzle; Numeriqo is the app. It names sixteen techniques and teaches each on a real grid, its hints draw the argument instead of filling in the answer, and grids go up to 9×9. One purchase, no subscription, no ads.