Stars like Ariana Grande, Cody Simpson and Taylor Swift look so cool (and have so much confidence!) while they're up on stage, that it's hard to believe they could ever feel uncool or nerdy. But — SURPRISE! — that's exactly what they think!
That's right — some of your fave stars have confessed to being nerds and M has the scoop on it all. Which star is totally Harry Potter obsessed? Which star calls herself "an 85-year-old"? Click through the gallery to find out, M Girls!
So what's YOUR nerdiest confession of all time? Share it with us in the comments!