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


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


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.

What’s New

Version 2.0

This version improves performance and stability.

Ratings and Reviews

4.8 out of 5
320 Ratings

320 Ratings

ChrisPost1 ,

Fun game

SumSudoku is a fun game, and challenges your mind. The controls work well as a phone or tablet game. Conceptis constantly works to evolve and improve the interface.

There are many other Conceptis games in the App Store. Like this app all of them offer one free puzzle a week, in addition to the several free ones that are given upon initial download. Additional games can be purchased outside of these for a reasonable price. Conceptis apps don’t have annoying ads like many other free to play software.

rsdofny ,

Best user interface in Suduko

1) dual input pads - one pad for notes and another for actual input. It saves a lot of time in toggling between the two for a lot of games
2) accurate reverse moves - people will make mistake and can have the comfort that they can restore the original position
3) magic note option - I have it on all the time. It removes the tedious steps in doing everything manual
4) the X button is great because it removes all your personal notes when I make mistake in creating wrong note
5) area calculator to list all possible alternatives

Area for improvements:
1) colorize the areas - it is very hard to see the border lines
2) calculator allowing user to input just sum and number of cells. This will compliment the area calculator.

Developer Response ,

Thank you very much for your feedback and suggestions! We took a note of these ideas, and will consider when we have our next app review.

Evontrot ,

Great challenge

I really enjoy this game but found I went through the free games pretty quick which makes waiting for the weekly update seem to take forever. Couple of suggested updates:
1. Let me change the basic colors, or at least provide options beside tan.
2. Instead of a pay as you go model let me have an option for a one-time pay option with all puzzles and updates included. New puzzles aren’t expensive but they will add up quickly.

App Privacy

The developer, Conceptis Ltd., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Used to Track You

The following data may be used to track you across apps and websites owned by other companies:

  • Identifiers

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

  • Identifiers
  • Usage Data

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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