Aspect ratio calculator

Solve for the missing dimension and identify common ratios.

Aspect ratio
16 : 9

Exactly 16:9

Decimal
1.77778

1.78 : 1

Megapixels
2.07
Orientation
Landscape
1920 × 1080

Resize keeping this ratio

Matching height
720
Result
1280 × 720
ScaleWidthHeight
0.25×480270
0.5×960540
0.75×1440810
1.5×28801620
38402160

Standard ratios

Common sizes

How it works

An aspect ratio is width divided by height, expressed in the smallest whole numbers that give the same quotient. 1920 ÷ 1080 simplifies to 16 : 9 by dividing both by their greatest common divisor, 120.

new height = new width × (height ÷ width)

Why 16:9 won

It is the geometric mean of the two formats television had to serve when the standard was set: 4:3 broadcast and 2.35:1 cinema. Choosing the middle minimises the total wasted area when letterboxing or pillarboxing either one.

Cropping versus stretching

Changing the aspect ratio of existing content means either cropping (losing edges) or distorting (everyone gets wider). Fitting content into a different ratio without either means adding bars. There is no fourth option.

Vertical video is not a mistake

9:16 exists because phones are held upright. For anything intended primarily for a phone screen, vertical uses the full display rather than a third of it.