Aspect Ratio Calculator
Work out the missing dimension that preserves an aspect ratio. Enter the original width and height plus one new dimension, and the other follows — the arithmetic that stops resized images looking squashed.
Free, no signupRuns entirely in your browser
Input
Result
- Calculated Dimension
- New Height (H2) = 720px
- Aspect Ratio
- 16:9
- Decimal Ratio
- 1.7778 : 1
- Original Width (W1)
- 1920px
- Original Height (H1)
- 1080px
- New Width (W2)
- 1280px
- New Height (H2)
- 720px
About
What the Aspect Ratio Calculator does
The ratios worth memorising: 16:9 for video and most screens, 4:3 for older displays and many camera sensors, 1:1 for square social posts, and 1.91:1 for link preview images. Knowing which one a platform expects saves a lot of cropping.
How it works
Using the Aspect Ratio Calculator
- 1Enter the original width and height.
- 2Enter the new width or the new height.
- 3The ratio is calculated from the original dimensions.
- 4The missing dimension is derived from that ratio.
- 5The result keeps the proportions unchanged.
Use cases
What people use it for
- Resizing an image to a fixed width for a layout
- Working out video dimensions for an embed
- Checking a crop matches a required ratio
- Scaling a design to a different canvas size
FAQ
Frequently asked questions
6 related
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