Pure Sudoku

CLEAN. SMART. ADDICTIVE.

Killer Sudoku online

Killer Sudoku starts with cage sums, then becomes pure logic.

Killer Sudoku adds dotted cages to the normal Sudoku grid. Each cage total narrows the candidates, while every row, column, and 3x3 box still uses digits 1 through 9 once.

Practice on Pure Sudoku Read the Killer Sudoku guide
Rule
Cage digits add to the clue
Still true
Rows, columns, boxes use 1-9
Best first step
Find small cages and fixed sums
Cages first

Use the smallest cage totals to remove impossible combinations early.

No guessing

A fair Killer Sudoku is still solved by logic, not trial-and-error.

Practice path

Warm up with Hard Sudoku, then apply the same candidate discipline to cages.

Quick rule

Every cage is a sum clue layered onto a normal Sudoku grid.

Killer Sudoku works because the cage totals and the normal 1-9 rules cross-check each other. A two-cell cage that totals 3 can only be 1 and 2. A three-cell cage that totals 24 must use high digits.

  • Start with two-cell and three-cell cages.
  • Eliminate cage combinations that repeat in the same row, column, or box.
  • Use Hard Sudoku practice when candidate tracking feels noisy.

Next steps

Hard Sudoku Sudoku strategies Daily Sudoku Killer Sudoku guide

Practice now

Open Pure Sudoku and train the core logic.

Use Hard or Expert boards to sharpen the candidate discipline Killer Sudoku needs.

Open Pure Sudoku Try Hard Sudoku