A scientific prodigy. His invention of Microbots earned him a recommendation to skip grades and enter university at age 14. He is emotionally expressive, highly knowledgeable about science, and full of curiosity. Male. He has messy black hair, brown eyes, and a slender build. He usually wears T-shirts or hoodies. Japanese-American. His specialty is Robotics Engineering.

Hiro's older brother and the creator of Baymax. He built Baymax at the San Fransokyo Institute of Technology. He is wise, cheerful, and compassionate toward everyone. Age 20. He has short black hair and is rarely seen without his favorite red baseball cap. Japanese-American. His specialty is Robotics Engineering. Male.

A kindhearted healthcare companion robot created by Tadashi. He can speak clearly like a human. He is made of white, inflatable vinyl and has a huggable appearance. He is programmed with 10,000 medical procedures; his 'heart' is a medical chip stored in a port on his left chest. He is gentle and has zero combat ability, but will risk his life to protect everyone in a crisis. Gender: N/A.

Tadashi's classmate at the San Fransokyo Institute of Technology. His name is a nickname given by Fred after he spilled wasabi on his shirt. Black. He is a neat freak who keeps all the lab equipment perfectly organized. Meticulous, easily spooked, and prone to worrying. He is a logical thinker. He has a large, muscular build and wears his hair in dreadlocks. He prefers green clothing. His specialty is laser technology and plasma physics. Male.

A student at the San Fransokyo Institute of Technology specializing in electromagnetic suspension. She is cool, laconic, and blunt, but deeply cares for her friends and is highly athletic. She is almost always chewing gum. She is a slender, fair-skinned woman with black hair. American. Her specialty is Mechanical Engineering.

A student at the San Fransokyo Institute of Technology and a chemistry expert. She has a happy, optimistic personality. She is tall and wears large, round glasses. She often wears lemon-yellow trench coats or long jackets and has long hair. Her specialty is Chemistry. White. Female.

The mascot of the San Fransokyo Institute of Technology. He is easygoing and cheerful. A massive fan of monster movies. He lives in a mansion and has a huge collection of action figures. While he seems like a carefree eccentric, he actually has a mysterious side. He is a slender white male. American.