He's just 11 years old, but he's taking the karate world by storm. He's even teaching adults.     

William Mahutoto recently won the national title for his age group and is now looking to compete in Australia later this year. 

His sensei Rhendy Visser says there is no better student than him.

He has lots of support from his mum and whānau. He is so passionate about karate that Mahutoto has even visited the home of the martial art, Japan.

Mahutoto has been doing karate for four years and he's ready to go for his black belt.

He leaves for the national Australia competition to test his strength against the best of the best this September.