ABC Tools
DPI & Pixel Size Calculator illustration

DPI & Pixel Size Calculator

Computes the pixel density of a screen from its resolution and diagonal, converts pixels to physical print size at a given DPI, and the pixels needed to print a given size.

Read the full guide to this tool

300 DPI is the usual print standard; 150 is fine for posters viewed at a distance.

Notes

  • PPI = √(width² + height²) / diagonal. Marketing "Retina" begins around 220 PPI at laptop distance.
  • DPI matters only when a physical size is involved; an image file by itself has no DPI, just pixels.

Explore the idea

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Read the full guide for the explanation behind it

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