Why Does Aspect Ratio Matter?
When you resize an image without maintaining its aspect ratio, the result is a stretched or squished visual. Our calculator ensures you always scale proportionally — critical for Instagram posts, YouTube thumbnails, print design, and responsive web layouts.
1. What aspect ratio should I use for YouTube thumbnails?
16:9 (1280×720px minimum). This is the standard widescreen ratio used across virtually all modern video platforms.
2. What ratio do Instagram posts use?
Square posts: 1:1. Portrait: 4:5. Stories/Reels: 9:16. Using the wrong ratio causes automatic cropping that may hide key content.
3. What does the decimal ratio mean?
It's width divided by height. A 16:9 ratio has a decimal of approximately 1.7778. Useful for CSS aspect-ratio property and canvas calculations.
4. Why is 4:3 called 'standard'?
It was the dominant TV and monitor ratio from the 1930s through the early 2000s. Most legacy content, presentations, and older video footage uses 4:3.
5. How do I use the scale calculator?
Enter a target width OR height in the 'Scale from Ratio' section and click outside the field. The tool automatically calculates the other dimension to maintain the source ratio.