Killer Sudoku is a free browser game on SolitaireFelt, built for a short break that can stretch into a long session. There is no download, no sign-in, and no backend: the puzzle runs in this tab and your best results stay in local storage on your device. That keeps the page fast, private, and easy for Google to crawl as a real game page rather than an empty iframe.
Classic sudoku plus dotted cages that must sum to the clue. It sits in our Sudoku & Numbers collection because people already search for this mechanic by name. The rules below match the familiar version of the game, with original board art and a full felt table for play.
How to play Killer Sudoku
Fill 1–9 so each row, column, and 3×3 box is unique. Dotted cages show a sum; digits in a cage cannot repeat and must add to that clue. No given digits — the cage sums are the puzzle.
Tips
Start with cages of only two cells — they pin a unique pair. Box lines still work; cages just add extra elimination.
If you enjoy Killer Sudoku, open the related games under this page. A full niche catalog — solitaire variants, mahjong layouts, daily sudoku, word puzzles, and board games versus a computer — is what makes SolitaireFelt worth bookmarking instead of a three-page demo.
