Missed a day? Each past puzzle stays available in the daily killer sudoku archive, listed by month.
Why medium every day
A daily puzzle should fit around the rest of the day. Medium is the level where killer sudoku stops being only about the obvious cages: you'll need pointing and claiming, naked pairs, and innie/outie pairs, where the rule of 45 leaves two unknown cells in a row, column or box and tells you their sum.
It never asks for the long multi-house sums of our hard puzzles or the wings and fish of expert. If you find the daily grid comes easily, the hard and expert killer sudoku sets are the next step. If it's a stretch, the medium set on the medium killer sudoku page gives you 20 more at the same level to practice on.
The rules in brief
- Digits 1 to 9 once each in every row, column and 3×3 box.
- Each cage's digits add up to its total.
- No digit repeats within a cage.
- No digits are given: every number comes from the cage sums.
A routine that works on the daily grid
Open with the cages that have one combination. A 3 or 4 in two cells, a 16 or 17 in two cells, a 6, 7, 23 or 24 in three cells: pencil those digits in before you place anything.
Then work the rule of 45 box by box. Add up the cages that lie wholly inside a box; if one or two cells are left uncovered, 45 minus that total is their value or their sum. Medium grids usually give you two or three of these early, and each one opens a different corner of the board.
When the arithmetic dries up, go back to scanning rows and columns for singles, and look for two cells in a house that share the same two candidates. Keep the killer sudoku cheat sheet handy for the less familiar totals, such as 15 in four cells or 20 in three.
Made fresh, checked the same way
The daily puzzles come from the same generator as the rest of the site. Each is proven to have one solution and graded by our step-by-step solver, which confirms that medium techniques are needed and that nothing beyond them is. If you're new to killer sudoku altogether, read how to play killer sudoku first; it takes a few minutes and makes the daily grid far less daunting.