Printable Killer Sudoku Puzzles

What is in the printable Killer Sudoku PDFs?

There are four free PDFs, one per level: Easy, Medium, Hard and Expert. Each holds 100 killer sudoku puzzles on 63 US Letter pages: a cover with the rules, two puzzles to a page on pages 2 to 51, and the solutions, nine to a page, from page 52. The pages are black and white. Every cage is a dotted outline with its total in the top-left corner, and the grid has no digits printed in it: the cages are the only clues.

The rules are the ones on each cover and on our Killer Sudoku page: every row, column and 3×3 box holds 1 to 9 once, the digits in a cage add up to its total, and no digit repeats inside a cage. The rules of Killer Sudoku guide covers the edge cases.

There is no email form and no account; the link opens the file. Like the rest of our printable sudoku, the sheets are free to print and photocopy for personal and classroom use.

How were these killer sudoku puzzles made and checked?

We made them. Every puzzle was dealt by the generator behind our online Killer Sudoku game, then handed to a second program: a solution counter we wrote separately from the generator, which searches a puzzle for a second answer. A puzzle with two answers, or one the counter could not settle, would have been thrown away and another dealt in its place. None had to be. All 400 were proven to have exactly one answer at the first deal.

If you printed these files before October 2026, you have an older set, made by an earlier version of our generator. We later caught that version dealing boards with more than one answer, 28 of 60 Hard and 39 of 60 Expert in our test, and on such a board a correct grid can disagree with the answer key. We fixed the generator and replaced all four PDFs at the same links.

How do the Easy, Medium, Hard and Expert PDFs differ?

The levels change the cages, not the rules. Easy draws cages of one or two cells, Medium up to three, Hard up to four and Expert up to five, and fewer, larger cages mean fewer totals that give their digits away. We ran all 400 printed puzzles through our technique solver, switching techniques off one at a time to see which each puzzle cannot do without:

The 100 puzzles in each PDF, as printed: cages per puzzle is the median, one-cell cages a share of all cages, and the next three columns count puzzles. “Need the rule of 45” means our solver finished the puzzle with it and not without it. “Beyond our solver” puzzles still have one answer, but take longer reasoning than its techniques include.

Easy is nearly half given. Six cages in ten are a single cell, which hands you about 35 of the 81 digits before you start, and every other cage is a pair. Cage totals with naked and hidden singles finish all 100: a gentle way to learn how cages read, not a real killer workout. From Medium on, one-cell cages fall to about six a puzzle and the arithmetic starts to matter. Where cage totals and singles stall, our solver reaches for locked candidates, pairs and the rule of 45, and on 11 Expert puzzles it needs that rule across two or three rows, columns or boxes at once.

Where do you start on a printed killer sudoku?

With a pencil, in this order. Write in the one-cell cages. Then mark the cages whose total allows only one set of digits: two cells making 3, 4, 16 or 17, three cells making 6, 7, 23 or 24, and the other extremes in our Killer Sudoku combinations guide. Then look for a quieter kind of cage, one whose total allows several sets that all share a digit. Puzzle 1 of the Hard PDF has two of them, both totalling 8 in three cells, and with the one-cell cages they place two 1s straight from the printed page.

On this puzzle, singles and cage totals place seven digits, these two among them, and then stop. Any one more technique finishes it: naked or hidden pairs and triples, a cage’s digits locking into one row or box, or the rule of 45. The Killer Sudoku game page draws that last one on a real board, and our Killer Sudoku tips and strategies guide puts the techniques in order.

How do you print killer sudoku so the cages stay readable?

• Paper. The pages are US Letter. On A4, choose “Fit to page” in the print dialog: the page shrinks by about 3% and nothing is cut off.
• Only the pages you need. Puzzles 1 and 2 are on page 2, 3 and 4 on page 3, and so on, so pages 2 to 6 hold Puzzles 1 to 10. Their answers are on pages 52 and 53.
• Black and white. Nothing on the pages depends on colour. If the dotted lines come out faint or broken, turn off draft or toner-saving mode.
• Reading the cages. Each dotted line runs just inside its own cage, so where two cages meet you see two lines side by side. A cell inside its own small dotted square is a one-cell cage.
• Pencil marks. Each grid is about 11 cm (4.35 in) wide, so a cell is about 12 mm across. A cage’s total sits in the top-left corner of its first cell, where a 1 goes in the usual 3×3 layout of pencil marks; keep your marks to the bottom of the cell.
• The margins. There is about 5 cm of white space on each side of a grid: room to list a cage’s possible sets (“8 in 3: 125, 134”) without crowding the cells.

How do you check your killer sudoku answers?

The answers are at the back, nine to a page in puzzle order: Puzzles 1 to 9 on page 52, 10 to 18 on page 53, and so on to Puzzle 100, alone on page 63. The answer grids show the 81 digits without the cages.

You can also check without looking. Because each puzzle has exactly one answer, a filled grid in which every cage adds up to its total with no repeated digit, and every row, column and box holds 1 to 9, is the grid in the answer key. Check the cages first: one that adds up wrong points straight at the mistake, and a row that does not add up to 45 is wrong somewhere.

Stuck rather than finished? Cover the answer grid and uncover one row or one box instead of reading it all; a single digit is often enough to get going again. If you would rather have each digit checked as you enter it, the online game deals boards from the same generator and marks a wrong digit red at once, and the daily Killer Sudoku gives everyone the same board each day. For a killer from a newspaper or book, our Killer Sudoku solver takes the cages and totals, solves the puzzle and says whether it has one answer.