The milestone on Friday came after a week of birthday messages poured in for the beloved environmentalist.
Charles and Camilla shared a carousel of photographs of Attenborough on the official royal family Instagram account.
"Wishing Sir David Attenborough a very happy 100th birthday," the caption read.
"Enjoy your special celebration this evening!"
Former England footballer Beckham also marked the environmentalist's big day with a post on his Instagram account with the caption: "Happy 100th Birthday to our National Treasure."
A number of stars, including Morgan Freeman, Dame Judi Dench and Spice Girl Geri Halliwell-Horner, have joined in the celebration and teamed up with conservation charity WWF, lending their voice for a moving birthday tribute.
The one-minute video, which includes Sex Education star Asa Butterfield, Merlin star Miranda Richardson, and presenter Liz Bonnin, features a spoken word reinterpretation of the Louis Armstrong classic What a Wonderful World.
It comes before a live event at the Royal Albert Hall, which will feature music from the naturalist's programs along with stories and reflections from public figures and leading advocates for the natural world, to celebrate Attenborough's centenary.
Attenborough said in a recorded audio message shared the night before his birthday that he was "completely overwhelmed" by the birthday greetings and that he thought it would be celebrated quietly.
Others paying tribute to Attenborough included Prime Minister Keir Starmer who previously said: "He is a true national treasure and a pioneer in his field - may his work continue to inspire people of all ages for years to come."
Attenborough has been inundated with messages from environmental and animal charities who marked his milestone with PETA renaming a "wise" bull who was among the first rescued through PETA India's Delhi mechanisation project, to Sir Attenbullock.
Britain's Natural History Museum revealed the night before Attenborough's birthday that a new species of wasp native to the Patagonian lakes of Chile, was named Attenboroughnculus tau after the environmentalist.
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