Want KenKen Ad-Free? — FIND OUT MORE    Why do we have ads?

Why are there ads?

We would love to provide everyone an ad-free experience, but we do need to generate revenue to cover at least some of our overhead. We're trying to be as reasonable as possible, and it also allows us to continue to offer you an option to access KenKen puzzles for free. For those who prefer an Ad-Free playing experience, we have an option for just pennies-a-day and it can be canceled anytime. BONUS! KenKen Premium also allows you to Track Your Progress, Join The Leaderboard, Save Puzzles, and more. Please consider this option for the best experience.

In addition, we continue to offer -- pro bono -- our KenKen Classroom Program which provides free KenKen puzzles and lessons to over 1 million students weekly. Revenue we raise from advertisements and subscription sales allow us to keep the program going, plain and simple. So thank you for supporting these teachers and students by supporting us. We all appreciate it.

×

Frequently Asked Questions:

TROUBLESHOOTING? CLICK HERE

  1. What do the words "KENKEN" mean?
  2. Are there multiple solutions to each KENKEN puzzle?
  3. I think I found a mistake in a puzzle!
  4. How can I contact KENKEN Customer Service?
  5. Why do you have advertisements on this site? I came here to play puzzles, not look at ads!
  6. Do I get refund if I cancel my subscription?
  7. What is a “target number”?
  8. What is a "cage"?
  9. Can I repeat a number within a cage?
  10. Does it matter in what order I put numbers into a cage?
  11. If there is only one square in a cage, what do I do?
  12. Why are some lines dark and some lines lighter?
  13. Do I need math skills to solve KENKEN puzzles?
  14. How do I start solving a KENKEN puzzle?
  15. Can the puzzles be solved without guessing?
  16. I’m new at KENKEN and need some help. What do you have for me?
  17. I signed up KenKen Classroom Program and I don't receive any emails. Why?
  18. Where can I find instructions to play the online puzzles?
  19. Do you have mobile versions?
  20. I have narrowed down the possible numbers for a square. Is there any way to note this online?
  21. I don’t always like clicking on things! Can I enter or delete numbers and notes using my keyboard?
  22. What is with the purple and yellow squares?
  23. When I click on a square, what do the "X" and "eraser icon" mean in the number ring?
  24. Can I save a puzzle that I haven’t finished?
  25. How I can delete my account?

FAQ Answers

TROUBLESHOOTING

  • Using Chrome and having a problem seeing a puzzle properly?

    You may be using Chrome version 11.9.900.170 which is Chrome's Beta Flash player. We are unable to support products in the beta stage, and ask you to install Adobe Flash version 11.9.900.152. For details to install that version, please go to http://www.adobe.com/software/flash/about/.

  • If the site isn't displaying properly, you may need to clear your browser.

    * How to clear the cache: http://www.wikihow.com/Clear-Your-Browser's-Cache It may also be necessary to restart your computer.

    Be sure you allow cookies and javascript for the kenken.com site. * How to enable javascript and cookies

  • Why aren't my puzzles loading?

    Here are a few things to try: Reload/refresh the web page. If that doesn’t work, make sure you have the latest version of Adobe Flash Player. Still not working? On your browser, empty the cache and clear the history. If all else fails, contact us and we’ll try to figure it out together.

  • My puzzles won’t print at all. What’s wrong?

    If you are using Firefox as your browser, click on "Print Problems" just below the PRINT button. [Note: I do not see this option on Firefox.] If you are not using Firefox, make sure you have the latest version of Adobe Flash Player. Still not working? Try printing from your browser’s file menu rather than clicking the printer icon below the grid. Or try switching to another browser. If all else fails, contact us and we’ll try to figure it out together.

  • If the above doesn’t resolve the issue, let us know which browser you’re using (and which version). Send us a screenshot of the issue. * How to send a screenshot

1. What do the words "KENKEN" mean?

"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!)

2. Are there multiple solutions to each KENKEN puzzle?

No! We create each KENKEN puzzle so that there is only one possible way to put the numbers in the squares. (As for no two snowflakes being alike, well, we’re still checking on that.)

3. I think I found a mistake in a puzzle!

First of all, that’s not a question, frequently asked or not. 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).

4. How can I contact KENKEN Customer Service?

You see down at the bottom of the page, where it says “Contact Us” in smaller type? You can always click there. But right now, we’ll make it even easier: You can 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!

5. Why do you have advertisements on this site? I came here to play puzzles, not look at ads!

We want anyone who enjoys KenKen to be able to play, regardless of financial situation. That’s why we offer free puzzles to you, and it allows us to support education through our free KenKen Classroom Program for teachers. The revenue from ads makes this possible. It also allows us to keep improving the site and develop great new features.

However, if you want a completely ad-free playing experience, just step up to our Premium Membership for just pennies a day!

6. Do I get refund if I cancel my subscription?

You may cancel your KENKEN PREMIUM membership at any time. 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.

7. What is a “target number”?

The target number is the small number in the upper left corner of a heavily outlined group of boxes (called a “cage”). It is usually followed by a math operation (+, –, x, ÷). So, for example, the notation 6+ means that the numbers in the cage should add up to 6. The notation 48x would mean that multiplying the numbers in the cage should give you a product of 48.

8. What is a "cage"?

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.

9. Can I repeat a number within a cage?

Yes, a number may be repeated within a cage as long as it is not repeated within the same row or column.

10. Does it matter in what order I put numbers into a cage?

The order does not matter—just make sure not to repeat a number in a row or column. So, 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. Now, as for putting on your socks and shoes, those have a specific order!

11. If there is only one square in a cage, what do I do?

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.

12. Why are some lines dark and some lines lighter?

No, your eyes aren’t playing tricks on you. The dark lines outline a cage. The lighter lines separate squares within the same cage.

13. Do I need math skills to solve KENKEN puzzles?

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 addition, subtraction, multiplication, and division. You'll be able to pick which operation(s) you want in your puzzle.

14. How do I start solving a KENKEN puzzle?

Every KENKEN player has his or her own style. 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

15. Can the puzzles be solved without guessing?

We guess so! It’s true: With logic, basic math, and a little perseverance, any KENKEN puzzle can be solved. There is no guesswork 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.

16. I’m new at KENKEN and need some help. What do you have for me?

Watch our Videos page for two separate how-to lessons (one starring Will Shortz, New York Times crossword editor). We also have a step-by-step text tutorial You’ll be an expert in no time, and ready to move onto our next frequently-asked question!

17. I signed up KenKen Classroom Program and I don't receive any emails. Why?

If you have not received your email with the link to the KenKen Classroom (KKCR) puzzle set, it’s likely it got caught in a spam filter, or blocked by your computer’s firewall. If possible, check your spam/junk folder and check your firewall settings with filters adjusted to allow mail with KenKen in the subject line, and/or accept mail from kenken.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 associated with the Constant Contact server that we send KKCR mails from.

Please let us know if this resolves the issue. If you prefer we edit your account to send the mails to an alternative email address, please write us with the information to classroom@kenken.com.

All mail from KenKen is sent from:

IP Range: 208.75.123.0 - 208.75.123.255

CIDR: 208.75.123.0/24

Network/Netmask: 208.75.123.0 255.255.255.0

Specific IPs sending from this range:

208.75.123.1 coi001.confirmedcc.com

208.75.123.2 coi002.confirmedcc.com

208.75.123.3 coi003.confirmedcc.com

208.75.123.103 coi103.confirmedcc.com

208.75.123.130 ccm22.constantcontact.com

208.75.123.131 ccm23.constantcontact.com

208.75.123.132 ccm24.constantcontact.com

208.75.123.133 ccm25.constantcontact.com

208.75.123.134 ccm134.constantcontact.com

208.75.123.135 ccm135.constantcontact.com

208.75.123.161 ccm26.constantcontact.com

208.75.123.162 ccm27.constantcontact.com

208.75.123.163 ccm38.constantcontact.com

208.75.123.164 ccm39.constantcontact.com

208.75.123.165 ccm165.constantcontact.com

208.75.123.166 ccm166.constantcontact.com

208.75.123.167 ccm167.constantcontact.com

208.75.123.168 ccm168.constantcontact.com

208.75.123.169 ccm169.constantcontact.com

208.75.123.170 ccm170.constantcontact.com

208.75.123.171 ccm171.constantcontact.com

208.75.123.172 ccm172.constantcontact.com

208.75.123.173 ccm173.constantcontact.com

208.75.123.174 ccm174.constantcontact.com

208.75.123.175 ccm175.constantcontact.com

208.75.123.176 ccm176.constantcontact.com

208.75.123.177 ccm177.constantcontact.com

208.75.123.178 ccm178.constantcontact.com

208.75.123.179 ccm179.constantcontact.com

208.75.123.180 ccm180.constantcontact.com

208.75.123.181 ccm181.constantcontact.com

208.75.123.182 ccm182.constantcontact.com

208.75.123.183 ccm183.constantcontact.com

208.75.123.184 ccm184.constantcontact.com

208.75.123.185 ccm185.constantcontact.com

208.75.123.186 ccm186.constantcontact.com

208.75.123.193 ccm33.constantcontact.com

208.75.123.194 ccm34.constantcontact.com

208.75.123.195 ccm35.constantcontact.com

208.75.123.196 ccm36.constantcontact.com

208.75.123.197 ccm197.constantcontact.com

208.75.123.198 ccm198.constantcontact.com

208.75.123.200 ccm200.constantcontact.com

208.75.123.201 ccm201.constantcontact.com

208.75.123.202 ccm202.constantcontact.com

208.75.123.225 ccm29.constantcontact.com

208.75.123.226 ccm30.constantcontact.com

208.75.123.227 ccm31.constantcontact.com

208.75.123.228 ccm32.constantcontact.com

208.75.123.245 mail245.nutshellmail.com

208.75.123.250 ccm37.constantcontact.com

18. Where can I find instructions to play the online puzzles?

You’ll find detailed instructions by clicking on "Tips to Play Online" on home page or simply clicking here.

19. Do you have mobile versions?

App-solutely we do! Visit our KENKEN Store to download the right version for you, whether it’s iPhone, iPod Touch, iPad, Android or Kindle .

20. I have narrowed down the possible numbers for a square. Is there any way to note this online?

There is a “Notes box” left side of the grid. Click on the possible numbers from that bar. 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!.

21. I don’t always like clicking on things! Can I enter or delete numbers and notes using my keyboard?

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.

22. What is with the purple and yellow squares?

When you move your mouse over a square, it turns purple. When you click on a square, it turns yellow.

23. When I click on a square, what do the "X" and "eraser icon" mean in the number ring?

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”.

24. Can I save a puzzle that I haven’t finished?

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! You can start from here.

25. How I can delete my account?

To cancel, click on "Account" and follow the simple cancellation instructions. No refunds or credits for partial months.

If your question is not answered, please contact customercare@kenken.com

Want KenKen Ad Free?
Click here

JOIN US

  • Twitter
  • Google+
  • Facebook
  • KenKen

CONTACT US

General questions & Concerns: customercare@kenken.com

KENKEN Classroom Program:
classroom@kenken.com

Licensing:
rights@kenken.com

International inquiries:
international@kenken.com

Welcome to KENKEN!

No matter what you're looking for — learning or fun — KenKen.com has it! Free online puzzles. Cool math games. Number games. (More addictive than Sudoku or Kakuro? You decide!) Educational games for kids. Visit our For Teachers section for math teacher resources, our free KenKen Classroom program, and a message from Tetsuya Miyamoto, the Japanese educator behind KenKen. Miyamoto, chess master David Levy, and the rest of Team KenKen have crafted these math puzzles into great games for learning and brain training. Need even more KenKen? Check out our Will Shortz Presents books. Try our mobile app on iPhone and iPad or our Kindle version. Play on the New York Times puzzle page and NCTM website. Regardless of why, how, or where you play, KenKen are the math puzzles that make you smarter!

Sincerely,
Team KenKen