Justin Long was 30 in Alvin and the Chipmunks: The Squeakquel when he played the character 'Alvin (voice)'.
That was over 14 years ago in 2009.
Today he is 45, and has starred in 76 movies in total, 35 of those since Alvin and the Chipmunks: The Squeakquel was released.
In Alvin and the Chipmunks: The Squeakquel, I think Justin Long looks: