Daily Killer challenges, massive puzzle archives, and the tools to master cage-sum logic.
Killer Sudoku looks intimidating — cages with target sums, no given numbers — but it's actually more beginner-accessible than it first appears. The sum constraints give you more information than a classic grid, and the Rule of 45 provides a powerful solving shortcut once you know it. Our complete Killer Sudoku guide covers everything you need to get started.
The sites below are the best dedicated Killer Sudoku resources online, from daily puzzles to deep archives of competition-grade grids.
The premier app used by Cracking the Cryptic for variants.
The ultimate tool for creating and sharing your own Sudoku variants.
The premier portal for hand-crafted Sudoku variants.
Exceptional puzzles from the world's best setters.
Master the logic of cages and sums with this popular variant.
A reliable hub for daily Killer Sudoku challenges.
Large variety of logic puzzles including high-quality Sudoku.
Sudoku's math-heavy cousin, perfect for logic fans.
Focuses exclusively on irregular regions (jigsaws).
Includes unique variants like Sudoku X and Hyper Sudoku.
Browse our full hand-curated directory of 100+ Sudoku sites, apps, and books.