Airbnb founder Nathan Blecharczyk and his wife Elizabeth Blecharczyk

At 32, Nathan Blecharczyk is one of the youngest billionaires on the list, thanks to his role as cofounder and CTO of Airbnb. But his youth is something he recognizes could empower him to make bigger changes.

In his giving pledge, Blecharczyk and his wife, Elizabeth, write: "We are humbled to find ourselves at a young age in an extremely privileged place. We recognize that the world has many real challenges and that we are in a unique position to have significant positive impact. We feel a responsibility to share our good fortune, and we pledge to dedicate the majority of our wealth over time to philanthropy."