SumSudoku: Killer Sudoku

In-app purchases
2.12K reviews
Content rating
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About this game

Play a crossover variation of Sudoku and Kakuro! SumSudoku, also known as Killer Sudoku, are addictive logic puzzles best described as a cross between Sudoku and Kakuro. Using pure logic and simple add/subtract calculations, these fascinating puzzles offer endless fun and intellectual entertainment to puzzle fans of all skills and ages.

Each puzzle consists of a 9x9 Sudoku grid containing areas surrounded by dark borders. The object is to fill all empty squares so that the numbers 1 to 9 appear exactly once in each row, column and 3x3 box, and the sum of the numbers in each area is equal to the clue in the area's top-left corner. In addition, no number may be used in the same area more than once.

The game includes helpful features such as showing possible sum number combinations in an area and pencilmarks to make temporary placement of numbers in the grid.

To help see the puzzle progress, graphic previews in the puzzle list show the progress of all puzzles in a volume as they are being solved. A Gallery view option provides these previews in a larger format.

For more fun, Conceptis SumSudoku includes a Weekly Bonus section providing an extra free puzzle each week.


• 90 free SumSudoku puzzle samples
• Extra bonus puzzle published free each week
• Multiple difficulty levels from easy to very hard
• Puzzle library continuously updates with new content
• Manually selected, top quality puzzles
• Unique solution for each puzzle
• Hours of intellectual challenge and fun
• Sharpens logic and improves cognitive skills


• Unlimited check puzzle
• Unlimited hints
• Show conflicts during gameplay
• Unlimited Undo and Redo
• Show possible sum combinations option
• Pencilmarks feature for solving hard puzzles
• Autofill pencilmarks mode
• Highlight Excluded Squares option
• Lock number on keypad option
• Concurrently playing and saving multiple puzzles
• Puzzle library sorting and hiding options
• Graphic previews showing puzzles progress as they are being solved
• Portrait and landscape screen support (tablet only)
• Track puzzle solving times
• Backup & restore puzzle progress to Google Drive


Conceptis SumSudoku have also become popular under other names such as Killer Sudoku, Sumdoku and Sumoku. All puzzles in this app are produced by Conceptis Ltd. - the leading supplier of logic puzzles to printed and electronic gaming media all over the world. On average, more than 20 million Conceptis puzzles are solved each day in newspapers, magazines, books and online as well as on smartphones and tablets across the world.
Updated on
Jan 29, 2023

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
This app may collect these data types
App info and performance
Data isn’t encrypted
You can request that data be deleted
2.12K reviews
Meganity Sliver
December 3, 2022
Good puzzle game, the pencil marks system is excellent. No ads, no extra chaos, just good logic puzzles, with good ramps of difficulty between each level set. I love that part but.. Wish I could change the colors- pale yellow on white is difficult, at best, to discern, especially with no dark mode. Lowering the screen brightness only makes the yellow even more difficult to see. This is painful at times. Otherwise this would be an amazing game.
2 people found this review helpful
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Conceptis Ltd.
December 16, 2022
Thank you for your feedback, and we are looking how to add Dark Mode and how to improve the color schemes. We hope to come out with a better interface in one of our future updates.
Lillie Griffith
November 3, 2022
I love this game and have been playing it for a few years. When I recently upgraded my phone, I was getting a recurring error when trying to restore my progress. The support team has since resolved the issue, for which I'm eternally grateful, but I have to give a huge shoutout to Dave specifically for being so responsive, kind, and helpful in our emails discussing the bug and possible fixes. Thank you!
7 people found this review helpful
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Conceptis Ltd.
November 16, 2022
Hi Lillie. Actually it is us who should thank you, for your quick reporting and accurate and detailed information which helped us find and fix the bug!
Karina Hart
August 25, 2022
This game is great and has just gotten better over time. The few things I was missing in gameplay I either found were already there or got added over time (such as auto filling pencil marks and crossing off combinations). My one remaining suggestion would be to offer different colors to show selected numbers. The yellow on beige combo is super hard on the eyes at times.
6 people found this review helpful
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What's new

This version improves performance and stability.