Free Aspect Ratio Calculator Online
Use this free aspect ratio calculator to resize width and height while keeping the ratio. Fast, private, and works in your browser.
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What is Aspect Ratio Calculator?
Aspect Ratio Calculator works out a missing width or height so your dimensions keep the same ratio. It is handy for resizing images, videos, and thumbnails to common ratios like 16:9 or 4:3. The math runs in your browser.
How to use this tool
- Enter the original width and height (or a ratio).
- Enter the new width or height.
- Read the matching dimension that keeps the ratio.
Features
- Solve for a missing width or height
- Common presets like 16:9, 4:3, 1:1
- Keeps the exact ratio
- Instant results as you type
- Runs entirely in your browser
This tool runs in your browser. Your files and text are not uploaded to our servers, and we do not store your input.
Frequently asked questions
What is an aspect ratio?+
It is the proportional relationship between width and height, such as 16:9.
Can I use presets?+
Yes. Pick a common ratio like 16:9 or 4:3, or enter your own.
Is anything uploaded?+
No. The calculation happens entirely in your browser.
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