Kakuro Cross Sum Number Puzzle

Get smarter every day with 1,000+ hand-crafted kakuro puzzles. No guessing, ever.

Kakuro is a logic puzzle with numbers: a number crossword, also known as cross sums. Fill the white squares with the digits 1 to 9 so that each line adds up to its clue. A digit can't repeat within a line. You need simple sums and a bit of logic.

NO GUESSING Every puzzle has exactly one solution, and you can reach it with logic alone. Two independent solvers check each puzzle, and any puzzle that needed a guess was removed. If you get stuck, the puzzle is still fair.

HINTS THAT EXPLAIN WHY A hint marks the square to look at. Tap "Explain why" to see the technique and the reasoning behind it. Both are free. Still stuck? You can check your work or get a head start. The first time is free, and after that you watch a short video.

LEARN ONE TECHNIQUE AT A TIME Seven kakuro techniques are introduced as you progress: Magic Sums, Reading Both Lines, Working the Edges, Narrowing Candidates, Only One Fits, Locked Pairs and Balancing Rows. Each one comes with a worked example.

12 TIERS, FROM 5×5 TO 9×9 Answer one question about your experience and the game starts you at the right tier. New players get a short hands-on tutorial. There is no level select. When you finish a puzzle, the next one is ready.

DAILY PUZZLE A new kakuro puzzle every day, the same for everyone. Mondays are easy and Sundays are very hard. Beat the par time to build your streak, and play missed days from the calendar.

MADE FOR SOLVING • The whole board always fits on screen, so you never zoom or scroll • Notes for pencil marks, cleared automatically when you enter a digit • Repeated digits are highlighted as you play • No timer on regular puzzles, only on the daily puzzle • Works offline • Available in English, German, Spanish, French, Italian, Polish, Portuguese, Russian and Japanese

If you like sudoku, killer sudoku, number sums, cross maths or other maths puzzles, give kakuro a try.

Discovery signals