The original aspect ratio of Cinderella’s theatrical release was 1.37:1. This was the Academy ratio, the standard shape for most American 35 mm films before widescreen presentation became dominant.
Cinderella premiered in 1950, when television and changing cinema technology were beginning to pressure studios to make films look wider. Walt Disney’s feature therefore arrived in the conventional Academy format rather than the later widescreen ratios associated with many theatrical reissues.
A common mix-up is 1.33:1, which is a rounded shorthand often used for the same general television-era shape. The more precise Academy specification is 1.37:1. Another source of confusion is later presentation: Cinderella was rereleased in a wider 1.75:1 format, which does not describe its original theatrical composition.
The film’s 1950 release was especially important for Disney. After financially difficult wartime years and unsuccessful features such as Pinocchio and Fantasia, Cinderella became a major commercial success and helped restore the studio’s fortunes.