Oscar-nominated producer/singer Williams earned the title Best Use of Interactive Video for his 24 Hours of Happy promo, while Beyonce's website landed her the People's Voice award in the Celebrity/Fan category.
Hip-hop group De La Soul claimed the Webby Artist of the Year honour, and Arcade Fire scored the Best Music (Film and Video) prize for their Just a Reflektor promo.
Meanwhile, Beyonce's rapper husband Jay Z was applauded for Best Music App for his Magna Carter... Holy Grail album release initiative, and Justin Bieber's FunnyorDie.com Between Two Ferns chat with Zach Galifianakis was named Best Comedy: Long Form or Series.
Martial arts icon Jean-Claude Van Damme's The Epic Split commercial for Volvo Trucks was a triple winner, picking up the Best Viral Marketing, Best Online Commercial and Best Branded Entertainment Short Form awards.
The winners of the 18th annual Webby Awards, organised by bosses at the International Academy of Digital Arts and Sciences, will be presented with their prizes at a ceremony in New York on 19 May (14).
The honours are handed out annually to reward Internet pioneers and those who make the best use of the web.