Aspect ratio is a proportional relationship between the width and height of an image or graphic. It is usually expressed as two numbers separated by a colon, such as 4:3 or 16:9, where the first number represents the width and the second number represents the height. The aspect ratio is important because it determines the relative horizontal and vertical sizes of computer graphics.
Common aspect ratios include:
- 1:1, which is the square format used by Instagram
- 3:2 and 4:3, which are standard photo sizes
- 16:9, which is the standard widescreen aspect ratio used for video content
- 9:16, which is the vertical video format commonly viewed on mobile devices
Aspect ratio is not the same as image size, which refers to the width and height of an image. The aspect ratio is the relationship between those numbers. Different display sizes require different aspect ratios, and the most common aspect ratios have changed over time. For example, before flat-screen televisions, the most common aspect ratio was 4:3, based on the shape of a standard strip of 35mm film. Since 2010, an aspect ratio of 16:9 has become the standard for computer monitors and devices.
