The gig is to be held in September in New York City's Central Park to promote the Global Poverty Project.
Neil Young and Crazy Horse, K'Naan and Band of Horses are among the other headliners, with more expected to be added.
A lottery of 54,000 tickets will be held for people who document charitable acts on the Global Citizen website. No tickets will be sold for the event.
The Global Poverty Project hopes the concert will inspire 100,000 charitable acts before a United Nations meeting on poverty this autumn.
Patrick Carney of The Black Keys told The AP that his bandmates are very proud to take part in the concert.
"The scale of things that they're trying to do just felt really cool, and we're trying to get the ball rolling," Carney said.
"Especially with everything that's been going on for the last three years, I suppose, after the stock market crashed.
"There's attention on the amount of people living below the poverty line and the disparity between the rich and the poor and everything that's going on now... It just felt like the right time to do something."
Global Festival 2012 takes place on September 29.
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