Instant Aspect Ratio Calculator
Scale dimensions flawlessly or calculate the exact aspect ratio of any given resolution.
STEP 1
Set your desired aspect ratio (e.g., 16:9 or 4:3).
STEP 2
Change Width or Height to scale proportionately.
STEP 3
Or enter custom dimensions and click "Find Ratio".
ASPECT RATIO (W : H)
:
DIMENSIONS IN PIXELS (W x H)
×
Dimensions synchronized.
Why Use JustAspect?
Scaling UI containers, resizing background images, or exporting video timelines requires perfect mathematical proportions to avoid stretching or letterboxing. JustAspect computes proportionate widths and heights based on your defined ratio, or algebraically reverse-engineers the exact ratio of any custom resolution using Greatest Common Divisor (GCD) math natively in your browser.