[Daily Challenge] A Collection of Cipher Quiz Problems to Stimulate the Adult Brain
Cipher puzzles are an intellectual pastime that stimulate adults’ brains—perhaps you’re one of the many who enjoy them.
Even ciphers that seem difficult at first can trigger an “aha!” moment with just a small shift in perspective.
From ones solved by substituting letters to those that use numbers, there’s a wide variety to try.
They’re easy to enjoy during your commute or on a break, and perfect for a quick mental workout.
Why not dive with us into the world of cipher puzzles—a realm that satisfies your curiosity while helping to activate your brain?
- [For Elementary School Students] Cipher Quiz: Fun Puzzle Riddles
- [Interesting] Collection of Matchstick Quiz Problems
- A collection of challenging quizzes for adults [Difficult]
- Genius if you can solve it? Super-difficult Quiz Collection
- A math quiz for adults. Can you solve it?
- [Genius if you can solve it?] Insight and intuition: a challenging IQ quiz
- [Battle of Wits] Stimulate your intellectual curiosity! Quiz questions that get adults excited
- [Brain Training] Difficult Riddles That Even Adults Struggle With
- [Challenging and Fun!] Quizzes & Riddles for Adults
- Riddles for college students. Questions that test thinking and creativity.
- [Satisfying When Solved] Challenging Quizzes Recommended for Elementary School Students!
- [Trick Quiz] Quiz Questions That Excite Everyone from Kids to Adults
- Funny quizzes for middle school students. Quizzes that can liven up a middle school setting.
[Daily Challenge] Cipher Quiz Collection to Activate the Adult Brain (21–30)
Emoji Quiz

Let’s answer what character is being represented! Here are some emoji quiz ideas.
They’re easy, casual quizzes you can try in spare moments or during your commute.
However, the difficulty is high, so many people might find them quite challenging.
There are five questions in total, and each one has a time limit, so you’ll be on the edge of your seat.
If you prefer to think things through slowly, pause the video and take it at your own pace.
Give it a try!
Puzzle-solving IQ quiz

The key is inspiration! Here are some ideas for puzzle-solving IQ quizzes.
It’s a roughly 90-minute compilation video that’s perfect for times when you want to focus on puzzles, like on holidays or during your commute.
Once you figure out the answers, you’ll find yourself wanting to react with “I see!” or “So that’s it!”—it’s full of fun problems like that.
Try incorporating it into your brain training or your relaxing time on days off.
It’s great to tackle on your own, but it would also be a lot of fun to work on with close friends or family.
Classic standard IQ quiz

This is a standard IQ quiz.
If it’s too difficult, you can lose the motivation to solve it, right? At times like that, warm up with a quiz like this.
Doing so will make your thinking more flexible, and there’s no doubt you’ll be able to enjoy quizzes more.
Witty Letter Quiz

A great way to exercise your mind and train your brain! Here are some ideas for clever letter quizzes.
How about livening things up with brain-teaser quizzes that anyone—from children to seniors—can enjoy? The key to these puzzles is to focus on the colors of the letters and how they’re combined.
There are six questions in total, and within a 20-second time limit you’ll receive three hints.
The sense of satisfaction when you reach the correct answer using the hints is exceptional! It also sounds fun to try in a fast-buzzer format with friends, or to write your answers on boards and compete by the number of correct answers.
Exercise your brain with tricky riddles! Can you solve all the cipher quizzes within the time limit? Try it in 30 seconds!

In recent years, there’s been a rise in quiz shows on TV, and with the unprecedented puzzle-solving boom, more and more people are tackling quizzes in their daily lives.
Riddle-like brain teasers that you can’t solve at a glance require approaching the answer from multiple angles, making them great for brain training.
It can also be fun to test kinds of creativity you don’t often use in everyday life—like visualizing kanji or converting things into English.
These are mental exercises I especially recommend to adults, who tend to have stronger preconceptions.
Cipher Quiz

This is a video where you find answers hidden in codes that don’t make sense at first glance.
With a childlike perspective, observation, and creativity, the puzzles are easy to solve—so they might actually be harder for adults.
Try tackling them with your friends or family!
Cryptographic puzzle quiz

This is a collection of quizzes featuring lots of cipher puzzles.
These ciphers combine letters, numbers, illustrations, and symbols.
The moment they’re presented, you might think, “Huh?” and feel your mind go blank.
But if you think it through carefully, the words should come to you.
The time limit is short, so it’s easy to feel rushed.
Flexibility of thought is the key to solving them well.
Although it’s introduced as being for adults, the content is solvable even for elementary school children, so it might be fun to tackle them together as a parent and child.



