Pixel Proportion Calculator
Enter the original size and one target dimension. The calculator will keep the image proportion and compute the missing value.
What is pixel proportion?
Pixel proportion is the relationship between width and height in an image, video frame, banner, or UI asset. If you change one dimension and want the graphic to stay visually correct, the second dimension must be changed by the exact same scale factor. That prevents stretching and squishing.
How this calculator works
The tool uses simple proportional math:
- Aspect Ratio = width ÷ height
- Scale Factor = target width ÷ original width (or target height ÷ original height)
- Missing Dimension = original dimension × scale factor
Example: if an image is 1600 × 900 and you need width 800, the scale factor is 800/1600 = 0.5. So the proportional height is 900 × 0.5 = 450. Final size: 800 × 450.
Why proportional resizing matters
1) Cleaner visuals
Non-proportional scaling distorts logos, faces, icons, and interface elements. Keeping proportions preserves design quality.
2) Better responsive design
On websites, assets often need multiple sizes for desktop, tablet, and mobile. Proportional resizing creates consistent visual rhythm across breakpoints.
3) Faster production workflows
Designers, developers, and content teams can quickly generate accurate dimensions for hero images, social media creatives, and product photos without guesswork.
Common use cases
- Resizing website banners and blog featured images
- Creating social media posts for different platforms
- Preparing screenshots for app stores
- Scaling video thumbnails and presentation graphics
- Converting mockup dimensions for responsive UI components
Tips to avoid mistakes
- Always lock aspect ratio in your editor when possible.
- Avoid manually dragging both width and height unless you need intentional distortion.
- Round dimensions carefully for pixel-perfect UI work.
- When exporting, verify the final size and file format (PNG, JPG, WebP, SVG).
Quick FAQ
Can I enter both target width and target height?
Yes. The calculator checks whether your entries stay proportional. If not, it suggests corrected values.
What if my original dimensions are not integers?
Decimals are supported. This is useful for high-density design systems, scaled artboards, and precision layout work.
Does this calculator crop images?
No. It only calculates proportional dimensions. Cropping is a separate decision based on composition and framing.