How to Calculate Image Aspect Ratio Online
Need to resize an image to a specific width but keep it from looking stretched or squished? That means doing the aspect ratio math first - or letting a calculator do it for you.
What Is Aspect Ratio?
Aspect ratio is the proportional relationship between an image's width and height, usually written as two numbers like 16:9 or 4:3. As long as that ratio stays the same, an image can be scaled up or down to any size without distorting - stretching wider or squeezing taller than the original proportions.
How to Calculate Aspect Ratio Online
LovePDFImg's Aspect Ratio Calculator works out proportional dimensions instantly.
Enter your original dimensions and a new width or height - get the matching proportional value instantly.
- Open Aspect Ratio Calculator.
- Enter your image's original width and height, or upload the file to auto-detect them.
- Enter the new width or height you want.
- Get the matching proportional value to keep it undistorted.
Common Use Cases
- Resizing for a specific slot - fitting an image into a website banner, social media post, or template that requires an exact width, without stretching it.
- Planning a crop - figuring out what dimensions to crop to before you start, so the final image matches a required ratio like 1:1 or 16:9.
- Print sizing - working out what height corresponds to a specific print width at the correct proportions.
After Calculating
Once you know your target dimensions, use Resize Image to actually scale the file to that size, or Crop Image if you need to change the ratio itself rather than just scale it.
Key Takeaways
- Aspect ratio is the proportional relationship between width and height.
- Keeping the same ratio when resizing avoids stretching or squishing an image.
- Use the calculated dimensions with Resize Image to apply them.