Fans of throwback Nickelodeon shows like iCarly, Sam & Cat, Big Time Rush, Ned’s Declassified School Survival Guide, Victorious, Unfabulous and Zoey 101 are about to feel pretty old because most of the stars that they grew up watching are all grown up themselves now — and boy, do they look different.

Take Nat and Alex Wolff, for example. They starred in Naked Brothers Band when they were only 9 and 12 years old, and they’re 22 and 25! What about Josh Peck? The actor was only 17 years old when Drake & Josh premiered, and now he’s a full-fledged adult with a wife and a son!

Fans have truly had the pleasure of watching them grow up right in front of their eyes. J-14 went ahead and rounded up a bunch of then-and-now photos of some more fan favorite Nickelodeon guys, so prepare to be shook over how much they’ve all changed over the years.

Scroll through our gallery to uncover 30 Nickelodeon guys who look completely different now compared to when they first started on the network.

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