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.

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)
• Pencilmarks feature for solving hard puzzles
• 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


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 1.5

This version improves performance and stability.

Ratings and Reviews

4.8 out of 5
170 Ratings

170 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.

AJan39 ,

Great app!

I love almost everything about this app. I wish I could select multiple cells to enter the same numbers. But I love that the numbers are always in the same place within the cell, and the I can highlight a number to see remaining places.
Compared to other apps, prices are a little high but considering the hours I spend playing this I don’t mind paying.
Definitely my favorite version of this game.

LinkTheValiant ,

Solid work from Conceptis as always

This is an excellent implementation of the Sum variant of Sudoku. It is simple and easy to mark cells, and the control scheme is well-adapted both to phone- and tablet-size screens. The developers at Conceptis add new puzzle packs for purchase regularly. Add to that the free bonus puzzle each week and you have a highly worthwhile mobile experience. 100% recommend.


Conceptis Ltd.
16.3 MB

Requires iOS 8.0 or later. Compatible with iPhone, iPad, and iPod touch.


English, Japanese, Simplified Chinese

Age Rating
In-App Purchases
  1. Easy Starters
  2. Medium Starters
  3. Hard Starters


  • Family Sharing

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

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