The movie was filmed in the spring of 1982 (filming continued until at least July for reshoots) and released in 1983. With that in mind, here's a list of how old each actor was at the time of most of the major filming:

Patrick Swayze (Darry) - 29 turning 30 (Aug 18 1952)
Rob Lowe (Soda) - turned 18 on set (Mar 17 1964)
C. Thomas Howell (Ponyboy) - 15 (Dec 7 1966) *turning 16 very late in the year
Ralph Macchio (Johnny) - 20 (Nov 4 1961) *21 very late in the year
Matt Dillon (Dallas) - turned 18 on set (Feb 18 1964)
Emilio Estevez (Two-Bit) - 20 turning 21 (May 12 1962)
Tom Cruise (Steve) - 20 turning 21 (Jul 3 1962)
Glenn Withrow (Tim) - 28 (Nov 24 1953) *29 late in the year

Diane Lane (Cherry) - turned 17 (Jan 22 1965)
Leif Garrett (Bob) - 20 (Nov 8 1961) *21 late in the year
Darren Dalton (Randy) - turned 17 on set (Feb 9 1965)
Michelle Meyrink (Marcia) - 19 (Sep 1 1962) *20 late in the year

Rehearsals were held previous to the spring filming, in late 1981.

Tags: actors' ages, birthdays, outsiders movie
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