Puzzems

Medium Killer Sudoku

Medium Killer Sudoku puzzles add classic Sudoku steps such as pairs, triples and pointing, plus cage and unit interplay: a digit a cage must contain that is stuck in one line clears it from the rest of that line.

Mistakes: 00:00
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Start over?

This clears the board and the clock.

Medium puzzles need at least one of these techniques, and may use any easier one:

Pointing
Inside a box this digit fits only in one line, so it can't go elsewhere on that line.
Claiming
On this line the digit fits only inside one box, so it can't go elsewhere in that box.
Naked pair
Two cells share the same two candidates, so those digits leave the rest of their area.
Cage and unit
A digit this cage must contain sits in one line or box, or a line can only place a digit inside this cage. Either way, the marked candidates go.
Hidden pair
Two digits fit only in the same two cells, so those cells hold nothing else.
Naked triple
Three cells hold only three digits between them, so those digits leave the rest of their area.
Hidden triple
Three digits fit only in the same three cells, so those cells hold nothing else.

How to play

Killer Sudoku is Sudoku with no given digits. Instead, dashed cages cover the 9×9 grid, each with a sum in its corner: the digits in a cage add up to that sum and never repeat, and every row, column and 3×3 box still holds 1 to 9 once.

Every Killer Sudoku here has exactly one solution and can be solved by logic alone. Its level is the hardest technique it needs, from cage combinations and the rule of 45 at Easy to the rule of 45 across several units and pattern techniques at Hard.

  • Each row, column and 3×3 box contains the digits 1 to 9 once.
  • The digits in a cage add up to the number in its corner.
  • No digit repeats within a cage.
  • There are no given digits; the cages are the clues.

Playing on this site

  • Select a cell, then type a digit or tap it on the number pad. Arrow keys move the selection.
  • Turn on Notes (or press N) to pencil in candidates instead of answers.
  • A cage's sum sits in its top-left cell; its notes move down to make room.
  • Hint first points out any wrong digits, then names the next technique and shows where it applies before giving anything away.
  • Your puzzle is saved in this browser, so you can come back to it later.