The concert will be broadcast live on Facebook, YouTube, Twitter, Apple, Viacom, iHeart Media, ANC and TMC France.
The online streams will begin at 7pm on Sunday, May 4, while the BBC's TV coverage begins at 6:55pm and their radio broadcasts begin at 6:30pm, reported Digital Spy.
Ore Oduba, Sara Cox, Nick Grimshaw and Anita Rani will host for the BBC.
The star-studded event is being held to raise money for the victims and families who were affected by the Manchester terror attack, which took place at the end of Ariana's concert at Manchester Arena on Monday, May 22.