He graduated with a BA(Hons) degree in Visual Communication and Design from Middlesex University in 1994.

[3] Several of his picture books have featured on the BBC television series CBeebies Bedtime Stories.

[6] In March 2020, Biddulph began uploading twice-weekly draw-along videos to help children looking for things to keep them occupied whilst stuck at home during the COVID-19 pandemic.

The videos received millions of views worldwide,[7] and on 20 May 2020 Biddulph broke the Guinness World Record for the largest ever online art class when 45,611 households joined him in drawing a blue whale via his YouTube channel.

[8] Biddulph was named as a UK Point of Light by Boris Johnson, the Prime Minister, who said "As our country observed the toughest restrictions in living memory, you inspired the creative spirit of the nation with millions of families tuning in to your #DrawWithRob series and spending special time together honing their artistic skills.