LONDON - Rupert Grint has beaten the record for the fastest time to reach 1 million followers on Instagram.

According to the Guinness World Records, the Harry Potter actor managed the feat in just four hours and one minute after he joined the site on Nov 10.

The previous record was set by Sir David Attenborough, who had taken 43 minutes longer. The British broadcaster and naturalist hit 1 million followers in four hours and 44 minutes with his first post in September.

Before that, it was American actress Jennifer Aniston who had caused a meltdown on the social networking site when she joined last October. She had posted a selfie with the other five cast members of the sitcom Friends (1994 to 2004) - Lisa Kudrow, Courteney Cox, Matt LeBlanc, David Schwimmer and Matthew Perry.

She took five hours and sixteen minutes to reach seven figures.

Grint's first post was a selfie with his six-month old baby girl Wednesday.

The 32-year-old English actor wrote: "Hey Instagram.... only 10 years late, but here I am. Grint on the Gram! Here to introduce you all to Wednesday G. Grint. Stay safe, Rupert."

Harry Potter co-star Tom Felton, who played Draco Malfoy in the fantasy franchise, was among the first to reply: "Welcome Weasley, it's about time. Love to Wednesday xx."

After less than 24 hours on the social networking site, Grint had more than 2 million followers, including singer Ariana Grande and Attenborough.

Although there have been only three posts from him so far, he has already amassed more than 3.4 million followers and follows a mix of personalities, from environmental activist Greta Thunberg to Formula One champion Lewis Hamilton.

Grint and his long-time partner, actress Georgia Groome, announced the birth of their first child in May.

The pair met on the set of comedy Angus, Thongs And Perfect Snogging in 2008 and became a couple in 2011.