Few YouTubers have made math as captivating as Grant Sanderson, better known as 3Blue1Brown. Through his unique visualizations and passion for teaching, Sanderson has not only amassed a dedicated following but has also created a lasting impact on math education. In this interview, he shares how his channel came to be, the journey of creating the popular animation tool Manim, and the rewarding experiences that continue to fuel his passion.
How did you transition from studying math to becoming one of the most popular YouTubers in math education?
Grant Sanderson: I’ve always enjoyed teaching, explaining concepts, and exploring programming, especially during my undergrad. Toward the end of college, I felt an urge to create a personal programming project. At a hackathon, I put together some very scrappy Python code for visualizing functions as transformations. And with that original fondness for teaching, I decided to make a short animated lesson out of it.
That initial video wasn’t particularly polished, but I enjoyed making it, and I kept improving the code and producing more videos. Around that time, I connected with Khan Academy about creating lessons for them, which turned into a one-year fellowship. Working with them made me realize how impactful online teaching could be, which made me more committed to creating lessons that could reach a broad audience.
Manim has grown into a popular tool used by other educators. What were your original goals, and how do you feel about its development?
Grant Sanderson: Honestly, I’m as shocked as anyone that it’s become popular! Initially, Manim was just some rough code I wrote for my own animations. I made it open source mainly because so many people asked how I animated my videos, so I figured sharing the code would be an easy answer.
As time went on, I worked hard to improve it, keeping in mind that others might find it useful too. The true credit for making Manim accessible to others, though, goes to the Manim Community. They forked the project, creating a version that’s much better documented and more beginner-friendly. It’s been amazing to see Manim evolve into something that anyone can use.
Was there a particular video that made you realize you were on to something special with 3Blue1Brown?
Grant Sanderson: There wasn’t a single moment when I thought, “This is it.” I never expected the channel to gain widespread popularity. My initial idea was to showcase math topics that weren’t taught in school but might intrigue math enthusiasts.
One turning point, though, was probably the linear algebra series. I applied a visuals-first approach to real course material, something I hadn’t done before. It may sound strange in hindsight, but up until that series, I hadn’t considered the channel as an educational resource. The positive response to that series helped me see the potential for deeper, course-related content on the channel.
With a wide range of topics, from neural networks to the best Wordle starting word, how do you choose what to cover?
Grant Sanderson: I start with whatever sparks my own interest and curiosity. If I’m not genuinely fascinated by a topic, I doubt I could convey it in a way that excites others. So, I focus on topics that get me nerding out, hoping that enthusiasm comes through for viewers.
What have been some of the most rewarding moments you’ve had as a math communicator?
Grant Sanderson: Meeting students in person who express sincere gratitude is incredibly rewarding. Sometimes they thank me for specific series, especially linear algebra, or for inspiring them to fall in love with math.
What’s interesting is that people often mention videos I hadn’t thought of as major, which reminds me that what matters most isn’t always what gets the highest views. Hearing how these videos have impacted people’s lives—whether helping with a course or sparking an interest in math—is the most gratifying part of this journey.
Sanderson’s journey from coding a few scrappy animations to creating a world-renowned math channel is an inspiring testament to the power of passion and curiosity. For Sanderson, it’s all about igniting a spark of interest, both in himself and in his audience, and his work with 3Blue1Brown continues to make math an adventure of discovery for millions around the world.
Subscribe to 3Blue1Brown’s channel here. Recommend to us other science communicators you’d be interested in learning about at jiaps@iaps.info.