Killer Sudoku Generator

Printable killer sudoku puzzles in three sizes: 4x4, 6x6 and 9x9 grids split into cages, each with the sum of its digits, and no digit given. You can print one grid per page or four of the same size. Every puzzle has exactly one solution, and its answer key shows every digit.

Killer sudoku follows the rules of sudoku: each row, each column and each box holds every digit exactly once. But no digit is given: the grid is split into cages, outlined with dots, and the small number in the corner of each cage is the sum of its digits. A digit never repeats inside a cage. You start with the smallest cages, list the digits that can make each sum, and cross out the ones that do not fit. Killer sudoku combines the logic of sudoku with addition practice, and trains planning ahead and checking your work.

1. Choose the settings. Pick the size of the grid (4x4, 6x6 or 9x9), and one or four grids per page.
2. Make a new puzzle. Press New: a new puzzle appears at once, with the same settings. Each one comes from a random number, its seed, kept in the address of the page.
3. Print it. Press Print to print the page on A4 paper, or choose “Save as PDF” in the print window to keep it.
4. Get the answer key. Tick Show the solution: the same puzzle appears with its solution in orange, ready to print as the answer key.
5. Share it. Copy the address of the page: it always gives the same puzzle back.

Every killer sudoku has exactly one solution, checked by the generator, and it can be solved by logic alone, without guessing. The cages have two to four cells on the 4x4 and 6x6 grids, and two or three cells on the 9x9 grid; a cage of a single cell gives its digit. The page is made in your browser: nothing is sent to Zuzuzi, and it is free, with no sign-up.