Video Aspect Ratio Calculator
Audio & video · Done in 3 steps
- 1Enter a size
- 2
- 3
About
Find the aspect ratio of any resolution, calculate missing width or height, and work out letterbox or pillarbox bars for 16:9, 9:16, 2.39:1 and more.
How to use it
- 1Enter a width and height to see its simplified ratio.
- 2Pick a ratio and type one side to get the other.
- 3Use the letterbox section to see bar sizes when fitting one ratio into another frame.
- You give
- Pixel dimensions and/or a ratio
- You get
- Simplified ratio, missing dimension, bar sizes and crop loss
- Good to know
- Assumes square pixels (true for almost all modern video). Results are rounded to whole (optionally even) pixels.
- Privacy
- Processed on your device. Nothing is uploaded, stored or logged.
- Last tested
- 2026-10-28
FAQ
What's the height for 16:9 at 1280 wide?
720 px. Height = width × 9 ÷ 16. Type any width above to calculate it instantly.
Why round to even numbers?
H.264 and most other video codecs use 4:2:0 chroma subsampling, which needs even widths and heights.
How big are the black bars for a 2.39:1 film on a 1920×1080 screen?
The picture is 1920×803, leaving bars of about 138 px top and bottom. The letterbox section calculates any combination.
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