Aspect Ratio Calculator
Calculate and scale aspect ratios for images and screens
Table of Contents
How to Use
- Enter the original width and height
- Optionally enter a new width or height to scale proportionally
- Click calculate to see the aspect ratio
- View the simplified ratio and scaled dimensions
What is Aspect Ratio?
Aspect ratio is the proportional relationship between an image's width and height. It's expressed as two numbers separated by a colon (e.g., 16:9), representing the ratio of width to height.
Maintaining aspect ratio is crucial when resizing images or videos to prevent distortion and ensure visual quality.
Common Aspect Ratios
| Aspect Ratio | Common Use | Example Resolution |
|---|---|---|
| 16:9 | Widescreen HD video, modern TVs | 1920×1080 (Full HD) |
| 4:3 | Traditional TV, older monitors | 1024×768 |
| 21:9 | Ultra-wide monitors, cinema | 2560×1080 |
| 1:1 | Square images, Instagram posts | 1080×1080 |
| 3:2 | 35mm film, DSLR cameras | 3000×2000 |
| 9:16 | Vertical video, mobile stories | 1080×1920 |
How to Calculate Aspect Ratio
To calculate aspect ratio, divide both width and height by their greatest common divisor (GCD):
- Find the GCD of width and height
- Divide width by GCD to get the first number
- Divide height by GCD to get the second number
- Express as width:height
Example: For 1920×1080, GCD is 120. 1920÷120 = 16, 1080÷120 = 9, so the aspect ratio is 16:9.
Practical Applications
Photography & Video
- Cropping images without distortion
- Resizing photos for different platforms
- Video editing and export settings
- Print sizing and framing
Web & App Design
- Responsive image sizing
- Social media content optimization
- Thumbnail generation
- UI element proportions
Display & Screens
- Monitor and TV selection
- Projector setup
- Multi-monitor configurations
- Gaming display optimization
Frequently Asked Questions
- What's the difference between 16:9 and 4:3 aspect ratios?
- 16:9 is a widescreen format used in modern TVs and monitors, providing a wider viewing area. 4:3 is the traditional format used in older TVs and monitors, appearing more square-shaped.
- Will changing aspect ratio distort my image?
- If you crop or resize to a different aspect ratio, you'll either need to crop parts of the image or add letterboxing (black bars). To avoid distortion, always scale proportionally using the same aspect ratio.
- How do I maintain aspect ratio when resizing?
- Calculate the scaling factor by dividing the new dimension by the original dimension, then apply that factor to both width and height. Our calculator does this automatically when you enter a new width or height.
- What aspect ratio should I use for social media?
- It depends on the platform: Instagram posts work best at 1:1 (square) or 4:5 (portrait), Instagram Stories use 9:16 (vertical), YouTube videos use 16:9 (widescreen), and Twitter supports various ratios but 16:9 is common.