Aspect Ratio Calculator
Calculate missing pixel dimensions, aspect ratio proportions, and image scaling factors for design and media production.
About Aspect Ratios
An aspect ratio expresses the proportional relationship between a visual display's width and height, written as two numbers separated by a colon (such as 16:9).
Formula
New Height (H2) = (Original Height × New Width) / Original Width
Standard Media Aspect Ratios
- 16:9: Standard widescreen video (1080p, 4K UHD, YouTube)
- 9:16: Vertical mobile video (Instagram Reels, TikTok, YouTube Shorts)
- 4:3: Classic television, presentation slides, and retro video
- 1:1: Square social media feeds and thumbnail graphics
- 21:9: Ultrawide cinematic widescreen displays
Frequently Asked Questions
How do you find the simplest fractional ratio?
Divide both width and height by their greatest common divisor (GCD).
What happens if aspect ratios are misaligned during export?
The image or video will either be letterboxed (black bars), cropped, or distorted due to non-uniform stretching.
Does scaling down pixel resolution reduce file size?
Yes. Halving both pixel dimensions cuts the total pixel count and raw uncompressed raster data by 75%.
What is responsive aspect ratio CSS?
Modern web layout uses the CSS property aspect-ratio: 16 / 9; to maintain visual proportions automatically as container widths change.
Calculate in three steps
- 1Enter your valuesUse the fields above and check the units shown beside each input.
- 2Run the calculationSelect Calculate to refresh the result with your latest values.
- 3Review or shareCompare the result, reset the form, print it, or share this page.