Real age of Mark Ruffalo in 54
In the movie 54, Mark Ruffalo was:
30 years old
That was the real age of the celebrity according to our calculation.
The calculation of the shown age took into account the first day of the year in which the movie 54 was released:
January 1, 1998
And the day in which Mark Ruffalo was born:November 22, 1967
Since movies usually don't take more than one year to be released since the beginning of the filming process, Mark Ruffalo may have been one year younger or one year older than the shown age while some scenes of the movie were being filmed.