Aspect ratio calculator
Find a video's aspect ratio or calculate the missing width or height for the frame you need.
Runs entirely in your browser. No video file or upload is needed.
How to use
- Choose whether to find a ratio, width or height.
- Enter the known dimensions or select a ratio preset.
- Copy the result and use the dimensions in your editor.
Recording your Mac screen?
Framecast records your screen and adds zooms, a smooth cursor and captions for you. Free to try, pay once to export.
FAQ
Does this resize my video?
No. It calculates ratios and dimensions without opening or changing a video file.
Which presets are included?
The tool includes 16:9, 9:16, 1:1 and 4:5. You can also enter a custom ratio.
Why is a calculated dimension rounded?
Some ratios produce fractional pixels. The tool shows the exact calculation and a labelled whole-pixel approximation, which can slightly change the ratio.
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