Aspect Ratio Calculator
Simplify any width and height into a ratio, and find the matching height for a new width. Free, no signup.
Scan to open on your phone
Point your phone camera at the code to open this tool.
Simplify any width and height into a ratio, and find the matching height for a new width. Free, no signup.
How to use Aspect Ratio Calculator
- Open the toolNo signup and nothing to install; it works as soon as the page loads.
- Set “Original width”
- Set “Original height”
- Set “New width”
- Read the resultChange any input and the result is recalculated immediately.
Worked example with the defaults
- ASPECT RATIO · 800 × 450 keeps the same ratio
- 16:9
Nothing you enter leaves your device
All of the work happens inside your browser. Whatever you type is never packaged up and sent to a server, and no request this page makes carries it.
That makes it safe for contract amounts, personal details and internal documents you would rather not hand to a third party — close the tab and it is gone.
What this tool does not do
Aspect Ratio Calculator only does what a browser can do on its own — it talks to no backend service. So it keeps no history for you and syncs nothing across devices; if you need a record, copy or download the result.
It is also not a substitute for professional judgement. For legal, medical or tax decisions, treat the output as a starting point rather than a final answer.
Frequently Asked Questions
- What is a 16:9 aspect ratio?
- It means the width is 1.78 times the height. Common resolutions are 1920×1080 and 1280×720.
- How do I keep the aspect ratio when resizing?
- Enter the new width and the calculator returns the height that keeps the original proportions.