The Revenant is leading the race for the 2016 Oscars with 12 nominations, with Mad Max: Fury Road scoring 10.
Redmayne, nominated this year for his role as transgender pioneer Lili Elbe in The Danish Girl, won the 2015 Academy Award for his performance as Stephen Hawking in The Theory of Everything.
DiCaprio, the star of survival epic The Revenant, has been nominated four times but has yet to win an Academy Award.
The best actor category also sees nominations for Michael Fassbender for biopic Steve Jobs, Matt Damon for space saga The Martian and Bryan Cranston for Trumbo, in which he portrays real-life Hollywood screenwriter Dalton Trumbo.
Veteran British actress Rampling, who receives a nod for marital drama 45 Years, faces competition in the best actress category from Cate Blanchett for Carol, Brie Larson for Room, Jennifer Lawrence for Joy and Saoirse Ronan for Brooklyn.
The 88th Academy Awards, hosted by Chris Rock will be held at Hollywood's Dolby Theatre on 28 February.