Aspect Ratio Calculator
Simplify ratios or solve for a missing width or height.
Every calculation runs locally in your browser. Nothing you enter here is sent anywhere.
Simplified ratio
16:9
Decimal ratio
1.7778
At 800px wide, matching height is
450 px
Preview
For informational and educational purposes only — not professional or technical advice, and not a substitute for consulting a qualified professional about your specific situation. TrueMeasureKit is not liable for decisions made based on these results. See our Terms of Service.
Why aspect ratio matters
Aspect ratio is the proportional relationship between width and height — 16:9 for widescreen video, 1:1 for square social posts, 9:16 for vertical stories. Keeping the ratio constant while scaling prevents stretched or squashed images: multiply both dimensions by the same factor, or use the "scale to a new width" field above to find the exact matching height for a resize.
Frequently asked questions
How do I find the missing width or height for a target ratio?
Given one dimension and the desired ratio, the other dimension is solved by cross-multiplication — this calculator does that math directly so you don't have to, and also simplifies odd pixel ratios down to their simplest whole-number form.