About KenKen Math Puzzles
Play free online KenKen puzzles — also known as Calcudoku or Mathdoku — right in your browser. Like Sudoku, every row and column must contain each number once. The twist is the cages: small groups of cells outlined in bold, each with a target number and an operation. Fill a “12×” cage with numbers that multiply to 12, a “3−” pair with two numbers three apart, and the grid slowly locks into place.
It’s a puzzle of pure logic with a little arithmetic on top, which makes it satisfying for math fans and a gentle workout for anyone who wants to keep their mental math sharp. You never need to guess: every puzzle here has exactly one solution that you can reach step by step.
Start with a quick 3×3 or 4×4 to learn the ropes, then work up to the classic 6×6 and the tricky 7×7. There’s a new daily KenKen every day, with the same puzzle for every player, a global leaderboard and a shareable results grid.
How to play KenKen
- 1
Know your numbers
A 4×4 grid uses the numbers 1 to 4, a 6×6 uses 1 to 6, and so on. Each number appears exactly once in every row and every column — the same rule as Sudoku, but with no 3×3 boxes.
- 2
Read the cages
Each bold-outlined cage shows a target and an operation in its top-left corner. The numbers inside must combine to that target: 7+ means they add up to 7, 24× means they multiply to 24. For − and ÷ (always two cells), subtract or divide the smaller number from the larger one in either order.
- 3
Grab the free cells first
A cage with a single cell and just a number is a given — write it in. Then look for cages with only one possible pair, like 11+ on a 6×6 (only 5 and 6) or 3÷ on a 4×4 (only 1 and 3).
- 4
Pencil in the possibilities
Tap Notes (or press N) and jot down the candidates for cells you can’t fill yet. As rows and columns fill up, cross-check the notes and remove the numbers that can no longer fit.
- 5
Finish the grid
Keep combining the cage math with the row and column rule until every cell is filled. When the last number drops in, every cage lights up and your time goes on the board.
Controls
| Input | Action |
|---|---|
| Click / tap a cell | Select it |
| Number keys or the number pad | Enter a number |
| N or Notes | Toggle pencil notes (or hold Shift while typing a number) |
| Arrow keys | Move around the grid |
| Backspace, Delete or 0 | Erase the selected cell |
| U or Ctrl+Z | Undo |
| H or Hint | Reveal a cell (3 free per puzzle) |
| P or Esc | Pause and resume |
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KenKen tips and strategy
Hunt for one-way cages
Some targets can only be made one way. On a 6×6, two cells with 5− must be 1 and 6, and 30× must be 5 and 6. Place those pairs early — even if you don’t know the order yet, they rule those numbers out of the rest of the row or column.
Use the row total
Every row and column adds up to the same total: 10 on a 4×4, 15 on a 5×5, 21 on a 6×6 and 28 on a 7×7. If cages cover all of a row except one cell, subtract the cage sums from the total to find that cell.
Factor the products
Break × targets into factors. A three-cell 60× on a 6×6 needs a 5 (no other way to get a factor of 5), leaving 12 for the other two cells: 2 and 6 or 3 and 4. Big prime factors like 5 and 7 are especially revealing.
Watch the shape of each cage
Cells of a cage that sit in the same row or column must be different. An L-shaped cage can repeat a number in the corner-to-corner cells, so 4+ over three cells in an L could be 1, 2, 1 — but never in a straight line.
Look for pairs
If two cells in a row can only be 2 or 4, those numbers are taken — remove 2 and 4 from the notes in every other cell of that row. The same trick works for three cells sharing three candidates.
Know your − and ÷ options
On a 6×6, 2÷ could be 1-2, 2-4 or 3-6, while 3÷ is only 1-3 or 2-6. Subtraction pairs with a big difference are tight: 4− is 1-5 or 2-6.
Turn on mistake checking while learning
With Check mistakes on (in the settings menu), wrong numbers turn red straight away. Repeated numbers and finished cages that miss their target are always flagged, so you can switch checking off for a purer challenge.
Where KenKen comes from
KenKen was created by Japanese math teacher Tetsuya Miyamoto as a way for his students to practice arithmetic and logical thinking. The name comes from the Japanese word ken, meaning wisdom or cleverness — so KenKen is roughly “cleverness squared.” The puzzles spread to newspapers in Britain and the United States in the late 2000s and quickly became a daily habit for many puzzle fans.
The same style of puzzle is also published under generic names such as Calcudoku, Mathdoku and KenDoku. KenKen is a registered trademark; the puzzles on this page are our own originals in the same style, and we are not affiliated with the trademark owner.
How our puzzles and the daily KenKen work
Every puzzle starts from a random Latin square — a grid where each number appears once per row and column. We split it into cages of one to four cells, choose operations (− and ÷ only on two-cell pairs, and ÷ only when it divides evenly), then run a solver to make sure the puzzle has exactly one solution that can be found by logic alone. Anything ambiguous is thrown away. Each puzzle is graded Easy, Medium or Hard by how much reasoning it takes.
The daily KenKen is a 6×6 that’s the same for everyone. It starts gentle early in the week, gets trickier midweek and saves the hardest grids for the weekend. Finish it to extend your daily streak, see how your time compares, and share a spoiler-free grid of your solve. Your progress is saved automatically, so you can leave and come back later.
Sizes, scoring and leaderboards
- 3×3 — a warm-up for learning the rules (not ranked).
- 4×4 — quick puzzles, perfect for a coffee break.
- 5×5 — the first real challenge, with more cage combinations.
- 6×6 — the classic newspaper size and the daily puzzle.
- 7×7 — bigger products, longer chains of logic.
Your score is your solving time. Times for the daily puzzle and the 4×4 to 7×7 grids go on global leaderboards, and your personal best for each size is saved on your device. Using a hint reveals a cell but makes that solve unranked. If you enjoy number logic, try Sudoku, the Math Puzzles game or Nonogram, or browse more number games.
Frequently asked questions
What is the difference between KenKen and Sudoku?
Both ask you to place each number once in every row and column. Sudoku adds 3×3 boxes and gives you starting numbers, while KenKen uses cages with arithmetic targets instead, so you work out the numbers from the math clues.
What are Calcudoku and Mathdoku?
They are other names for the same type of puzzle. KenKen is a trademarked name, so many sites and newspapers use Calcudoku, Mathdoku or KenDoku for grids with arithmetic cages and the no-repeat row and column rule.
Can a number repeat inside a cage?
Yes, as long as the repeated numbers aren’t in the same row or column. In an L-shaped cage, the two cells at the ends of the L can hold the same number. In a straight cage, every number must be different.
How do subtraction and division cages work?
They always contain exactly two cells. Subtract the smaller number from the larger, or divide the larger by the smaller, and the answer must match the target. The two numbers can be in either order.
Does every KenKen puzzle have only one solution?
Every puzzle on this site does. Our generator checks each grid with a solver and keeps only puzzles with a single solution that can be reached by logical steps, so you never have to guess.
Is there a daily KenKen puzzle?
Yes. A new 6×6 daily KenKen appears every day at midnight your local time, and everyone gets the same puzzle. Difficulty rises through the week, and your result counts toward your daily streak.
Is KenKen free to play?
Yes. Every puzzle here is free, with no download or account needed. It works on phones, tablets and computers, and your progress and best times are saved on your device.