In no particular order, here is 15 hot young celebs . At the time of this post all these guys were under 30 .

Alex Pettyfer ( age 27 ) 

Liam Hemsworth ( age 27 )

Robbie Amell ( age 29 )

Keiynan Lonsdale ( age 25 )

Grant Gustin (age 27)

Harry Styles (age 23 ) 

Tyler Posey (age 25)

Tyler Hoechlin  (age 29)

Zac Efron (age 29)

Chris Brown (age 28 )

 Austin Butler ( 25 )

Zayn Malik ( 24 )

Dylan O’Brien ( 25 )

Justin Bieber ( 23 )

Luke Hemmings ( age 20 )