[Challenging and Fun!] Quizzes & Riddles for Adults
We’re introducing riddles and fun quizzes for adults!
When you hear “riddles” and “quiz questions,” you might think they’re for kids, but these days there are quiz shows that adults can enjoy too, making them fun for all ages.
In this article, we’ve put together some slightly challenging riddles and quizzes for adults.
They’re especially recommended for grown-ups, whose thinking can sometimes get a bit rigid!
Try them as brain training, too.
You might be surprised by how difficult they are!
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[Challenging and Fun!] Quizzes & Riddles for Adults (51–60)
Caesar Cipher Quiz
This is a quiz that uses the Caesar cipher, which creates a code by shifting letters by a fixed number.
For example, if you shift “WORLD” forward by 3 letters, it becomes “ZRUOG.” Even if a word looks meaningless at first glance, the key point is that you can reveal the original word by shifting back using the same rule.
To decode it, you need careful observation and patience to determine the correct shift amount, but the sense of accomplishment when you grasp the pattern can be addictive.
It’s perfect as brain training for adults, since you can have fun while honing logical thinking.
Once you get used to it, you can also encrypt your favorite words yourself and exchange them with friends, making it a quiz with a wide range of ways to enjoy.
A cipher riddle quiz using kanji
The combination of kanji and ciphers is a puzzle packed with brain-training elements that make the most of the depth of Japanese.
You’re given the reading of three kanji characters as a hint, and the challenge lies in how to use it.
It’s a riddle where you search for clues from a lined-up string of kanji.
Sometimes romaji serves as a hint, and answering while considering meanings tests your mental flexibility.
Simply knowing kanji isn’t enough—you need creativity and a shift in perspective, which is part of the appeal.
It’s a puzzle that lets you experience the fun of looking at kanji from an unusual angle.
A cipher quiz using mathematical formulas
A cryptic quiz that looks like simple addition but uses completely different logic to reach the answer.
Equations that seem nonsensical—like 3+7=“trauma” or 4+6+2=“sea slug”—hide tricks such as the ordering of letters or words.
It’s recommended to consider the problem from multiple angles, including letter order and wordplay.
Finding the answer tests your ability to think outside the box.
It’s not just about logical reasoning; a feel for language is also required, making it a quiz that gets your whole brain firing—and becomes addictive.
Answer the animal from the number code
This is a brain-teaser quiz where you deduce the name of a specific animal from what looks like a random string of numbers.
There are conditions like 11555 = dog, and you figure out the correct answer by using the hints hidden in the numbers.
As you solve the puzzles, you consider whether there’s a cipher rule and what the numbers mean in relation to the animal types, so flexible, outside-the-box thinking is required.
The key is to look at the problem from multiple angles.
Familiar numbers line up like puzzle pieces, creating a mystery that’s so engaging even adults will get hooked.
Quiz to find the hidden letters in the cipher
How many of these can you solve? “The Hidden Letters in Codes Quiz” is a seven-question intellectual challenge that unravels mysteries concealed in familiar words, kanji, and English spellings.
By interpreting characters from a different perspective than usual, you’ll arrive at surprising answers that make you think, “Aha!” These problems call for flexible thinking and flashes of insight, making them perfect for a mental workout or a quick refresh.
It’s an ideal, easy-to-try intellectual pastime for adults, suited to brief moments during commutes or breaks.
Trick riddle! If you don’t get tricked, are you a genius?
These days, many people may just take in information through their phones without thinking for themselves.
Among riddles, this set contains many trick questions.
Solving problems like these can boost academic ability and help prevent dementia, and it’s said to make your brain eight years younger.
Please give them a try.
Even if you come up with an answer that seems likely for a riddle, there’s a high chance it’s a trick.
By taking your time to think through the answer, you can stimulate your brain even more.
World Automaker Logo and Emblem Quiz
Here’s a common difference in how things are called by foreigners: what we in Japan call “Benz” is known as “Mercedes” abroad.
It seems that’s because not everything called “Benz” is the same “Benz.” Maybe it’s similar to calling all Japanese video games “Nintendo”? For car lovers, don’t miss this “Logo & Emblem Quiz.” You might recognize the big names like Mercedes, Ferrari, and Lamborghini, but once it gets a bit more obscure… Gather your car-enthusiast friends and have a blast with this quiz!
A puzzle kids can solve instantly! A challenging quiz for adults
If we compare adults and children, adults undoubtedly have the upper hand in physical strength.
But what about brainpower? The very assumption that “there can’t be problems children can solve that adults can’t” might itself be a sign of a rigid mind.
Here’s a quiz that pits you head-on against the uniquely flexible thinking of children.
For example, if 80 is 3 and 69 is 2, what do you think 41 would be? A child might instantly answer 0.
The correct answer is the number of circles in the digits.
There are plenty of other fun quizzes too—adults might really struggle!
An elementary school homework quiz that’s way too hard
Back when a university degree carried much more weight, just saying you were a college graduate would make everyone go “Wow!” Of course, in those days, going to university often came with certain social and financial advantages.
Even so, when did the image of university students as “carefree?” start to take hold? How about trying some “elementary school homework” that even college students struggle with? Questions like “What’s another name for a snake?” or “What’s a plant that resembles horsetail?”—there are plenty that leave even adults scratching their heads.
How many of these problems—impressive enough to make you think elementary school kids are amazing—can you solve?
Hard-to-read Japanese city names quiz
A common feature on quiz shows is the section on difficult kanji.
It almost always gets the crowd excited.
However, it’s a bit different from ordinary difficult kanji—in fact, even people with Level 1 Kanji Kentei certification apparently find it hard to read the tricky kanji used in people’s surnames and place names.
By the way, there are place names in my hometown like “Heki” and “Asago,” but since I’ve been familiar with them since childhood, I grew up without realizing they’re considered hard to read.
Their pronunciations are, respectively, “Hiki” and “Asso.” I’d love people who are good with kanji to give this quiz a try.
Maybe travel enthusiasts have a slight advantage.