Image Dimension Calculator
Scale dimensions while keeping the aspect ratio.
Input
This tool runs entirely in your browser. The data you paste or load is never uploaded.
Result
Enter your input, then run the tool.
About this tool
Calculates proportional width and height from an original size, and estimates print dimensions at a given DPI. Useful before exporting an image for print or fitting a banner into a strict layout.
How to use it
- Enter the original width and height.
- Enter one new dimension to calculate the other, or a percentage.
- Read the ratio, megapixels and print sizes.
Frequently asked questions
How do I keep the ratio exactly?
Enter one new side and leave the other empty; the second value is derived from the ratio and rounded to a whole pixel.
What DPI should I use for print?
300 DPI is the usual standard for photos and brochures; large posters can be viewed from further away and often work at 150 DPI.
Keep going
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