Several actors have played/portrayed Elizabeth Bennet & Mr. Darcy in both big screen and small screen since 1940 to this day (to date), but did you know, only one pair of EB/Darcy actors were exactly or rather the closest to their book counterparts?
Here's a compiled list (though the *LBD series pairing is included in both picture and the list below, their ages are in ??? since I don't know their ages at all as they are not listed anywhere, neither on their official sites, nor IMDB...my guess would be, they're either in the mid to late 20s or so...) to see which EB/Darcy pairing (of P&P actors) is accurate in terms of ages as their book counterparts...
The Elizabeth Bennet/Darcy actors' ages at the time their P&P adaptations were released were...
Keira Knightley (20) & Matthew Macfadyen (30) - Pride & Prejudice (2005)
Jennifer Ehle (26) & Colin Firth (35) - Pride and Prejudice (1995)
Greer Garson (36) & Laurence Olivier (33) - Pride and Prejudice (1940)
Elizabeth Garvie (23) & David Rintoul (32) - Pride and Prejudice (1980)
Kam Heskin (30) & Orlando Seale (30) - Pride and Prejudice (2003)
Aishwarya Rai Bachchan (31) & Martin Henderson (30) - Bride & Prejudice (2004)
Gemma Arterton (22) & Elliot Cowan (32) - Lost In Austen (2008)
In P.D. James' Death Comes To Pemberley novel, Elizabeth Darcy is 26 and Mr. Darcy is 34 (6 years after Austen's P&P novel)...
Lily James (26) & Sam Reilly (35) - Pride and Prejudice and Zombies (2015)