Free Aspect Ratio Calculator — Resize Without Distortion
Stretching is what happens when a size changes without its ratio. Enter any width and height and this calculator simplifies it to the clean ratio (1920×1080 becomes 16:9), names the common format if it matches one, and scales to any new width or height while keeping the other dimension proportional. Built for video exports, social crops, thumbnails, and screen sizes.
Aspect Ratio Calculator
Simplify ratios and scale widths and heights proportionally — no more stretched or squished videos and images.
1 Dimensions
2 Ratio results
📐 Results
How it works
The tool divides both dimensions by their greatest common divisor to simplify the ratio, converts it to a decimal for quick comparisons, and — when you give it one new dimension — multiplies by the original ratio to compute the matching other dimension, rounded to whole pixels. All math happens instantly in your browser.
Everyday uses
- Video editors — confirm export sizes for YouTube (16:9), Shorts/Reels/TikTok (9:16), and cinema (21:9).
- Designers — scale images and artboards without distortion.
- Social managers — get exact pixel sizes for 1:1 and 4:5 posts from any source image.
- Developers — preserve ratio for responsive embeds and video players.
Frequently asked questions
What aspect ratio are YouTube Shorts and TikTok?
9:16 vertical — 1080×1920 is the standard export size.
Why does my scaled height have rounding?
Pixels are whole numbers, so proportional heights round to the nearest pixel. A 1-pixel difference is invisible in practice.
Is 16:9 the same as 1.78:1?
Yes — 16 divided by 9 is 1.78. Film often writes ratios as x:1; video and web usually use the simplified fraction form.