An Australian schoolgirl who revealed she was transgender to her classmates in a heart-warming video on YouTube has been praised for her bravery.

Abbey Boon, formerly Ethan, came out to her classmates at Mowbray Heights Primary School in Tasmania on July 1.

Abbey starts her video by explaining she has felt different her whole life. Credit:YouTube

The video of the 11-year-old explaining her "secret" to the world has been viewed more than 5000 times, with her mother Melinda Miles claiming "many happy tears" were shed once Abbey became her true self.

In it, Abbey uses laminated signs to reveal the pressure she felt at her former school to fit in, before she found the courage and confidence to be herself.