Calcudoku
Past dailiesFill every cell so each row and column holds each digit exactly once, and the digits in every outlined cage make its target with the operation shown. Every puzzle has one solution you can reach by logic alone.
How to play Calcudoku
How to play
Tap a cell, then tap a number on the pad (or type it). On a 6×6 board use 1 to 6. Each digit appears once in every row and column. The digits in a cage must make the number in its corner: added (+), multiplied (×), or for two-cell cages the difference (−) or the quotient (÷) of the larger and smaller digit.
Repeats inside cages
A digit may repeat inside a cage as long as the two copies are in different rows and columns, so an L-shaped 5+ cage could be 1, 3 and 1.
Tips
Start with the cages that have few ways to be made: a two-cell 3÷ on a 6×6 board can only be 1 and 3 or 2 and 6. Then use the rows and columns: a digit that a cage must use in one row can't appear anywhere else in that row.
Hints that teach
Hint takes one logical step, applies it to the board and explains it in a sentence, such as which ways a cage can still be made. Cages that don't add up and repeated digits are marked with a stripe and a dot.
Questions
What are the rules of Calcudoku?
Fill an n×n grid with the digits 1 to n so no digit repeats in a row or column. The grid is split into cages, and the digits in each cage must make the cage's target using its operation: +, −, × or ÷.
Do − and ÷ cages work in either order?
Yes. Take the larger digit minus (or divided by) the smaller one. A 2− cage could be 3 and 1 in either order, and a 2÷ cage could be 2 and 4.
Does every Calcudoku here have exactly one solution?
Yes. Every puzzle is checked by two separate solvers that count solutions, and by a logical solver that proves it can be finished by reasoning at its difficulty level.
What do the difficulty levels mean?
Easy puzzles need cage combinations and singles. Medium 6×6 puzzles add pairs and cages that pin a digit to one row or column. Hard 7×7 puzzles need triples or an X-wing.
Is there a daily Calcudoku?
Yes. The daily puzzle is a 6×6 medium Calcudoku that is the same for everyone and changes at midnight UTC.