Harry Potter fans have listened to more than a billion hours of the series on Audible.
The books were added to the Amazon-run audio library seven years ago.
Stephen Fry, who narrates the UK version of the audiobooks, says he's astonished by the figures. "Almost every day someone will come up and tell me how important the audiobooks have been in their lives, and it means the world to me".
English singer and actor, Jim Dale narrates the books for the US.
Pottermore Publishing, says in one billion hours, you could listen to the seven books in the Harry Potter series more than 8-and-a-half-million times, or hypothetically go through Hogwarts School of Witchcraft and Wizardry more than 14-thousand times.