Historic and commonly used aspect ratios
* 1.19:1: "Movietone" - early 35 mm sound film ratio used in the late 1920s and early 1930s, especially in Europe. The optical soundtrack was placed on the side of the 1.33 frame, thus reducing the width of the frame. The Academy frame (1.37) fixed this by making the frame lines thicker. The best examples of this ratio are Fritz Lang's first sound films: M and The Testament of Dr. Mabuse. This is roughly the frame size used for anamorphic photography today.
* 1.25:1: Commonly used computer resolution of 1280x1024. Native aspect ratio of many LCDs. Also the aspect ratio of 4x5 film photos.
* 1.29:1: Ratio of US Letter size paper (11:8.5 inches), in landscape format.
* 1.33:1: 35 mm original silent film ratio, common in TV and video as 4:3. Also standard ratio for IMAX and MPEG-2 video compression.
* 1.37:1: 35 mm full-screen sound film image, nearly universal in movies between 1928 and 1953. Officially adopted as the Academy ratio in 1932. Still occasionally used. Also standard 16 mm.
* 1.414:1: Aspect ratio of standard ISO paper sizes (A4, A3, et cetera). Also the square-root of 2.
* 1.43:1: IMAX 70mm horizontal format.
* 1.5:1: The aspect ratio of 35mm film used for photography. Wide-aspect computer display (3:2). Used in Apple Powerbook G4 15.2" displays with resolutions of most recently 1440x960. Also the native NTSC DVD-Video resolution, 720x480, although most videos use non-square pixels for a 4:3 ratio.
* 1.6:1: computer display widescreen (8:5, commonly referred to as 16:10). Used in WSXGAPlus, WUXGA and other display resolutions.
* 1.618:1: the golden ratio.
* 1.66:1: 35 mm European widescreen standard, also Super 16 mm and Japanese HiVision. (5:3, sometimes expressed more accurately as "1.67".)
* 1.75:1: early 35 mm widescreen ratio, since abandoned.
* 1.78:1: video widescreen standard (16:9). Also used in high-definition television One of 3 ratios specified for MPEG-2 video compression.
* 1.85:1: 35 mm US and UK widescreen standard for theatrical film. Uses approximately 3 perforations ("perfs") of image space per 4 perf frame; films can be shot in 3-perf to save cost of film stock.
* 2:1: Univision System, developed by Vittorio Storaro, with the intention of making this a universal theatrical and television ratio. It never really went anywhere.
* 2.2:1: 70 mm standard. Originally developed for Todd-AO in the 1950s. 2.21:1 specified for MPEG-2 but not used.
* 2.35:1 : 35 mm anamorphic prior to 1970, used by CinemaScope ("'Scope") and early Panavision. The anamorphic standard has subtly changed so that modern anamorphic productions are actually 2.39, but often referred to as 2.35 anyway, due to old convention. No recent anamorphic films are 2.35. (Note that anamorphic refers to the print and not necessarily the negative.)
* 2.39:1: 35 mm anamorphic from 1970 onwards. Sometimes rounded up as 2.4. Sometimes referred to as 'Scope.
* 2.55:1: Original aspect ratio of CinemaScope before optical sound was added to the film. This was also the aspect ratio of CinemaScope 55.
* 2.59:1: Cinerama at full height (three specially captured 35 mm images projected side-by-side into one composite widescreen image).
* 2.76:1: MGM Camera 65 (65mm with 1.25x anamorphic squeeze). Only used on a handful of films between 1956 and 1964, such as Ben-Hur (1959).
* 4:1: Polyvision, three 35 mm 1.33 images projected side by side. Only used on Abel Gance's Napoléon (1927).
The evolution of film and TV aspect ratios
Comparison of three common aspect ratios constrained by the screen diagonal size (the black circle). The smaller box (blue) and middle box (green) are common formats for cinematography. The largest box (red) is the format used in standard television.
The 4:3 ratio for standard television has been in use since television's origins and many computer monitors use the same aspect ratio. Since 4:3 is the aspect ratio of the usable frame within the Academy format once the soundtrack had been taken into account, films could be satisfactorily viewed on TV in the early days of the medium. When cinema attendance dropped, Hollywood created widescreen aspect ratios to immerse the viewer in a more realistic experience and, possibly, to make broadcast films less enjoyable if watched on a regular TV set.