The calculation, without hidden assumptions
Aspect ratio is more useful when it can drive the next resize rather than simply label a frame. MAXScanner simplifies the source dimensions, calculates proportional target dimensions and can show the unused padding created when that source is contained inside another frame without cropping.
How to use this calculator
Enter the source width and height in pixels or any matching unit.
Choose whether to solve a new width from target height or a new height from target width.
Optionally enter a target frame size to see contained dimensions and horizontal/vertical padding without cropping.
Where people use it
- •Video and image resizing
- •Social-media format planning
- •Checking letterbox or pillarbox padding
Example: 1920×1080
The GCD is 120, so 1920:1080 simplifies to 16:9. A proportional 1280 px width produces 720 px height.
What the result does not assume
- •A simplified ratio does not guarantee the content was authored for that ratio; clean-aperture, anamorphic and pixel-aspect-ratio workflows can require more metadata.
- •The contain calculation adds padding rather than cropping. Cover/crop behavior is intentionally not mixed into this result.
Frequently asked questions
How do I simplify an aspect ratio?+
Divide width and height by their greatest common divisor.
What causes black bars?+
When source and frame ratios differ, containing the full source leaves unused space on two sides.
Does this resize the actual file?+
No. Use MAXScanner image/video tools after choosing the target dimensions.
Semantic next steps
Continue the calculation
These links move to a different input, formula or project stage rather than a keyword variation of this page.
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OpenFree publisher widget
Put this calculator on your website
Give readers the live calculator without rebuilding the math. Copy the responsive embed in one click, or customize width, height, border and corner radius before publishing. The branded MAXScanner attribution stays visible.
Calculator embed HTML
Paste this code into your page. Focus the code box to select it manually.
Keep the result connected to the real job
MAXScanner keeps the formula and assumptions beside the result so you can verify the number before using it in a drawing, estimate, specification, worksheet or document. Where a supplier, manufacturer, drawing or applicable standard owns a requirement, that source remains authoritative.