What age does your skin start age?

From the instant you are born it starts and continues your whole life.

Everyone is different. It is not like you have wrinkles or crowsfeet or anything. I have seen young people with gray hair or losing their hair in college. My boss' hair turned snow white in his 50's. But if someone stays in good shape in can be difficult to tell if they are 20 or 45 or older. Maybe is is just that with dark hair it shows up on your face faster (5 o'clock shadow) than those of us who are blond and can skip a day shaving.

Usually around late twenties. I think you look around 22/23 :)

You do look older than 21.

Everyone is different, but genetics are key. You'll age the way your parents did. My skin didn't really start to show age until I was about 30, and at 45 I still have no wrinkles. If it weren't for the graying hair I could pass for 35. :)

Don't stress about it. A moisturizer with an SPF of 30 or so would be beneficial.

Average is 30 years old, depends if you still produce oils on your skin because they reduce wrinkles.