"Ken" is the Japanese word for “wisdom.” So we like to think of “KenKen” as “wisdom squared.” (See? We told you the puzzle makes you smarter—you just learned some Japanese!)
No! We create each KenKen puzzle so that there is only one, single, unique solution. (As for no two snowflakes being alike, well, we’re still checking on that.)
First of all, that’s not a question! But we will answer it anyway! Our puzzles are created by a high-level artificial intelligence program called the Kenerator. For each puzzle, it verifies that the numbers in each cage produce the intended target number; that no number is repeated in a row or column; and that there is only one overall solution (i.e. one possible way to place the numbers in the squares). So to sum it up, we can assure you that there are no mistakes in our KenKen puzzles. It's been years, and no one has uncovered a mistake yet!
You simply click here! We want to make your KenKen experience as fun and clear as possible, so just let us know how we can help you!
We want anyone who enjoys KenKen to be able to play, regardless of their financial situation. That’s why we offer free puzzles to you, and it allows us to support education through our free KenKen Classroom Program which is provided free of charge to over 30,000 teachers. The revenue generated from ads makes this all possible. It also allows us to keep improving the site and develop great new features.
If you want a completely Ad-Free playing experience, you can upgrade to our Premium Membership for just pennies a day!
You may cancel your KenKen Premium Membership at any time, but we do not provide refunds or credits for any partial-month membership periods or unused portions of an annual membership. To cancel, visit our website and click on "Cancel Automatic Renewal" on the "Account" page. (We would be sad to see you go!)
The target number is the small number in the upper left corner of a heavily outlined group of squares (called a “cage”). It is usually followed by a math operation (+, –, x, ÷). This is the number that a user is supposed to have a cage add, subtract, multiply, or divide to, given the proper operation. So, for example, the notation 6+ means that the numbers in the cage should add up to 6, in any order, using addition. The notation 48x would mean that multiplying the numbers in the cage, in any order, should give you a product of 48.
That refers to one of the heavily outlined groups of squares in a grid. Every cage has a target number in the upper left corner. All cages (except single-square cages) have a math operation next to the target number. This is the operation that should be used when combining the numbers in the cage to produce the target number.
Yes, but not often. A number may only be repeated within a cage as long as it is not repeated within the same row or column. This only happens in irregularly shaped, or larger, cages.
No, the order does not matter—just make sure not to repeat a number in a row or column. For example, in a two-square cage, if the target number is 3 and the operation is subtraction, 1 and 4 can be placed in either order...the 1 on top or bottom in a vertical cage, or on the left or right in a horizontal cage.
You should smile, because these are the easiest cages to solve. We call them “freebies.” The target number (in the upper left corner) is the number you write in the cage.
No, your eyes aren’t playing tricks on you. The dark lines outline a cage (see question #8). The lighter lines separate squares within the same cage.
You don’t need to know the quadratic equation or be able to solve the Riemann hypothesis, but yes, basic math is involved. You’ll need to know addition, subtraction, multiplication, and division in order to solve KenKen puzzles. Luckily for you, users are able to pick which operation(s) they want in their puzzles.
Every KenKen player has his or her own style of solving KenKen puzzles. Many like to fill in single-square cages first. Cages that have only one possible set of numbers are good to look for. (For example, in a 4x4 grid, if there is a two-square cage with a target of 7+, we know the numbers will be 3 and 4.) For more tips, check our Beginners' Tutorial
It’s true: with logic, basic math, and a little perseverance, any KenKen puzzle can be solved. No guesswork is required. This doesn’t mean that a little trial-and-error isn’t helpful. That can come in quite handy to eliminate possibilities in larger puzzles.
Watch our Videos page for two separate How-To lessons (one starring Will Shortz, New York Times Crossword Editor and NPR Puzzle Master). We also have a step-by-step text tutorial. You’ll become an expert in no time, and be ready to move onto our more difficult puzzles!
If you have not received your email with the link to the KenKen Classroom (KKCR) puzzle set, it’s likely it got caught in your spam filter or blocked by your computer’s firewall. If possible, first check your spam/junk folder to see if it's there. Also check your firewall settings, making sure filters are adjusted to allow mail with KenKen in the subject line, and/or accept mail from kenken.com or kenkenpuzzle.com.
If there is no mail from us in the spam folder, we may have run into problems with your school's internal firewall blocking mails from us. Our KKCR weekly sets are sent via a mailing service called Constant Contact. Some domains find emails like this suspicious and block them. In this case, please contact your IT team to whitelist the following IP addresses or website URLs associated with the Constant Contact server from which we send KKCR mails:
If your program allows website URLs, copy the following URLs and add them to the whitelist:
If your program allows IP addresses, add these IP addresses to the whitelist:
220.127.116.11/22 (which is the same as 208.75.120.*, 208.75.121.*, 208.75.122.*, and 208.75.123.*)
Note: Some security programs will prompt you to restart your computer to allow the changes to take effect.
Please let us know if this resolves the issue. If you prefer, we can edit your account to send the mails to an alternative email address. If that works better for you, please write us with the new information to email@example.com.
You’ll find detailed instructions by clicking on the "Tips and Tricks" icon on the home page, or by simply clicking here.
There is a “Notes box” to the left of the grid. Click on the possible numbers from that box. The numbers will show up in small type in the square. For more details, see our online instructions. Want to repeat your note(s) in another square? You can simply drag the note from the first square to the second!
Sure! Once you’ve selected a square, you can press shift and a number key to enter (or delete) that number as a note. Or, to just enter a number in a square, press that number on the keyboard (no shift). To delete a number, press C.
When you move your mouse over a square, it turns purple. When you click on a square, it turns yellow.
If you change your mind about a number you’ve answered, clicking the eraser icon will delete it. If you want to hide the number ring, click “X”.
Yes! As a KenKen general member, you may save one free puzzle. If you are a KenKen Premium level you can save up to 20 puzzles! All you need to do is click the save icon at the bottom right of your puzzle, and it will be available to play later!
To cancel, click on "Account" and follow the simple cancellation instructions. No refunds or credits for partial months.
If your questions were not adequately answered, please feel free to contact firstname.lastname@example.org