Aspect Ratio Calculator
Easily compute the missing width or height to maintain a specific aspect ratio, or scale an existing size up/down by a percentage. Pre‑loaded with all common aspect ratios (16:9, 4:3, 1:1, 3:2, 21:9, 9:16) plus the ability to enter a custom ratio. Perfect for photographers, video editors, and web designers who need pixel‑perfect dimensions without leaving their browser.
How to Use
- 1Choose a preset aspect ratio (e.g., 16:9) or enter a custom ratio.
- 2Enter either the width or the height you already have, or provide both and a scaling percentage.
- 3The tool instantly displays the missing dimension, the equivalent scaled size, or a visual ratio comparison.
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Frequently Asked Questions
Can I calculate a new size after scaling by a percentage?
Yes. Enter the original width and height, then select the scaling percentage field. The tool will show the exact pixel values at that percentage, maintaining the original ratio.
What if I only know one side of the final image?
Simply select your desired aspect ratio, type in the known dimension, and the calculator will output the missing side in pixels.
Does this tool respect common video standards?
Absolutely. Presets include 16:9, 4:3, 21:9, and 9:16 (vertical), and you can manually input any ratio like 2.35:1 for cinema.