A new aspect ratio may discard part of a photo. Enter the source pixel size, the desired width-to-height ratio, and a planned print width to see how many original pixels remain and the resulting print resolution.

Formula: fit the target width:height ratio inside the source rectangle; retained % = crop pixels ÷ source pixels × 100; print PPI = retained crop width px ÷ planned print width in

Worked example

A 4,000 × 3,000 px photo cropped to 16:9 keeps 4,000 × 2,250 px. It retains 75% of source pixels, and a 10 in wide print uses 400 pixels per inch across the cropped image.

This is the largest centered rectangle

The calculation fits a target-ratio rectangle inside the source bounds and reports its whole-pixel dimensions. You may move that rectangle to keep the important subject, but the pixel count is the same. Rounding can make the displayed whole-pixel ratio approximate.

Cropping does not resample

Cropping removes outer pixels. It does not invent detail or resize the retained pixels. Adobe distinguishes cropping from resampling; export settings in an editor may subsequently change the pixel size.

PPI uses the cropped image

The displayed PPI uses the retained width and the print width entered here. It does not judge the viewing distance, printer, paper or acceptable quality. For a different print width, change that one input.

Explore the related calculation

For a different starting point, try the print scaling calculator or return to the main calculator. Browse the complete tool directory for this site.

Reference and corrections

The definitions and assumptions above follow these sources; the examples and calculator arithmetic are original to this page.

helpx.adobe.com reference

Found a problem? Email contact@pixelstoinches.org.

Aspect ratio crop resolution calculator

Enter your values

Result