Rupert Alexander Grint was born on August 24, 1988 in Hertfordshire, England, UK. He is the eldest of children with siblings consisting of James, Georgina, Samantha, and Charlotte. Rupert was born to Nigel Grint who was an ex-race car memorial dealer and Jo Parsons who is a homemaker.

He enjoys learning to ride the unicycle, riding quad bikes, drawing/sketching, golfing, swimming, and playing the guitar.

Before being cast in Harry Potter, he had only appeared in plays for school and his local theatre group, Top Hat Stage School, such as Peter Pan and Rumplestiltskin. As a young child, he was once cast in a play based on the story of Noah's Ark, as a fish.

As fan of the Harry Potter book series, young Grint was interested in getting a role in the movie. Like the other children who attended to the audition Rupert came in with a rap that promoted the character he was auditioning for, Ronald Weasley, and was chosen soon afterwards and like Ron Weasley, he has stated that he has a fear of spiders.

After completing the first Potter film, Harry Potter and the Sorcerer's Stone, he appeared as Alan A. Allen in the British comedy film Thunderpants (2002). He again starred as Ron Weasley in the Harry Potter sequel, HP and the Chamber of Secrets (2002), HP and the Prisoner of Azkaban (2004) and HP and the Goblet of Fire (2005).

In July 2004, Rupert left Richard Hale School, taking his GCSE examinations in, among others, Art and German.

In 2006 Grint starred in the coming-of-age story Driving Lessons with Julie Walters and Laura Linney, the movie is centred on Ben, the shy son of a vicar. The movie was released in the summer of 2006.

The filming of HP and the Order of the Phoenix started after Driving Lessons and the flim will be released on July 13, 2007.

Also known for his radio and television voice-over work, he appeared as Nigel Molesworth of the Baggy Trousers series for BBC Radio 4 (2006) and voiced Peter Pan in a BBC documentary.