4kiz Inc. 2025

Tokyo, Shibuya Ward

A social media platform for children under 15 that is more fun than games and more educational than school, connecting children around the world.
In recent years, 93% of junior high school students and 70% of upper elementary school students have their own smartphones, but all major social media platforms require users to be 13 years of age or older according to their terms of service. Children under 12 are lying about their age and violating the terms of service to use social media. As a result, sexual crimes and cyberbullying on social media are rapidly increasing, and no one is able to stop it.
That's why we provide a safe, age-appropriate social media platform for children under 15, where they can connect with peers authentically. Users can post short videos and images, and the platform features AI-powered automatic detection of inappropriate content, parental control functions, and other safety measures to achieve zero incidents of crime or bullying.

4kiz Inc. 's News & Column
NEW INFORMATION

4kiz Inc.'s Main Innovation
INNOVATION

Project to enhance safety by introducing AI sentiment analysis in social networking services for children

We will strengthen safety measures such as preventing defamation and bullying by introducing AI emotion analysis into our children's SNS.
By introducing AI emotion analysis technology, we can automatically detect malicious comments, insults, negative interactions, and self-deprecating expressions that do not trigger NG words. After review by the administration office, comments that violate the terms of service will be deleted or result in account suspension. Even in cases that do not warrant such severe measures, we will consider implementing algorithms to make negative expressions less visible to users.
We anticipate that this initiative will provide a valuable platform for children worldwide using our app, enabling safer, more positive interactions, and leverage our strengths to drive business growth.

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4kiz Inc. Representative Introduction
REPRESENTATIVE

Representative Katsuhiro Motoyama Katsuhiro Motoyama
Graduated from the Department of Intelligent Social Systems, Faculty of Engineering, University of Tokyo, and completed a master's degree in International Education Policy at the Harvard Graduate School of Education. Raised in an extremely poor family, he supported himself through part-time work from his first year of high school while his parents were absent from home. Without relying on cram schools or private tutors, he self-studied and was admitted to the University of Tokyo and Harvard Graduate School. He has studied a wide range of fields, from science to humanities, and from engineering to education.
At the Japan Foundation, one of Asia's largest international NGOs, he has been involved in education, human rights, international cooperation, support for people with disabilities, Paralympic support, and children's support programs, launching over 30 new initiatives. He has served as Director of the Paralympic Support Center, Team Leader of the Children's Support Team, and Team Leader of the Human Resources Development Team. He resigned in November 2021 and started his own business.
As the father of six children, he has taken four periods of parental leave. His hobby is engaging in fun activities with his children. As a blogger, he shares his unique perspectives on parenting and education on platforms like BLOGOS, generating significant attention.
He is the author of numerous books on the theme of “the revolution of learning,” including “Sōzō-kun and Picture Book Making” (KADOKAWA), “Child-Rearing to Foster Curiosity,” “The Ultimate Self-Study Method,” “The Ultimate Memorization Method” (Yamato Shobo), “16x Speed Study Method” (Kobunsha), “How to Learn to Keep Growing for Life” (Kaneki Publishing), and “Let's Talk About the Truth of Scholarships Now” (Poplar Publishing). " (Poplar Publishing), among others, with a cumulative total of over 300,000 copies sold. His works have been translated and published in countries such as South Korea, Taiwan, China, and Thailand, becoming bestsellers.
Main Achievements 2024: Runner-up in the Makino City-sponsored Makino Challenge Business Competition 2024 (Maki Challenge 2024)
2024: Selected as a finalist in the WE AT Challenge
2025: Winner of the Entertainment Division Award at the 10th Japan Entrepreneur Awards
Childhood Dream Become a leader who can guide Japan to become a country that contributes to the world.
Influential People, Things, and Events People: Ryoma Sakamoto, Masayoshi Son
Things: Books, social media
Events: Entrance exams for the University of Tokyo, studying abroad at Harvard
Motivation, Goals, and Ideal World I have six children. A few years ago, I bought my then 11-year-old daughter a tablet, and she began to enjoy drawing lots of pictures on it.
As a parent, I felt that if she could share her work with many people and receive feedback, it would motivate her and help her develop her talent further.
So, I looked into whether she could create her own account and post her work, but I found that no social media platform in the world allows users under the age of 13 to use their services. In this era where children naturally use smartphones and tablets, I was deeply surprised to find that there was no safe social media platform available anywhere in the world.
And I thought, “If children could safely share their passions and interests in a secure environment, it could help nurture their creativity and potential. If no one else is providing such a platform, then I will do it myself!” That's when I made up my mind.
Actually, I had already planned my life 50 years in advance when I was 18, and I had a vision of starting my own business in my 40s. At that time, I was exactly 40 years old, making it the perfect timing to start a business. Additionally, a respected investor I admire published a book on entrepreneurship, and I had the opportunity to participate in the entrepreneurship workshop held in conjunction with the book's release. This felt like the final push I needed to take the plunge.
With all these factors aligning, I decided to launch the “Safe and Secure Children's SNS for Kids” business.

4kiz Inc. Basic Informaton
BASIC
INFORMATION

Company Name 4kiz Inc.
Representative Name Katsuhiro Motoyama
Address 1-5-7 Ebisu, Shibuya-ku, Tokyo Showa Ebisu Building 504
Official Site and Social Media note
Instagram
Official Website
Facebook
YouTube
@4kiz_ | X (Twitter)
Founding Date December 1, 2021
Awards 2024: Runner-up in the Makino City-sponsored Makino Challenge Business Competition 2024 (Maki Challenge 2024)
2024: Selected as a finalist in the WE AT Challenge
2025: Winner of the Entertainment Division Award at the 10th Japan Entrepreneur Awards

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