Understanding DPI and Image Resolution

DPI stands for Dots Per Inch. It describes how many pixels are packed into one inch of physical space when an image is printed or displayed.

Higher DPI means more detail per inch. For example, a 300 DPI image printed at 1 inch square contains 300 × 300 pixels. For screen display, 72 to 96 DPI is common, while 300 DPI is the standard for high-quality prints.

On its own, DPI does not change the number of pixels in a digital image. A 1200 × 1600 pixel image is the same file size whether it is labeled 72 DPI or 300 DPI.

However, DPI matters when you need to print at a specific physical size. A 600 × 600 pixel image at 300 DPI prints as a 2 × 2 inch photo. At 72 DPI, the same image prints as an 8.3 × 8.3 inch photo with less detail.

1. Open the DPI & Size Calculator.

2. Enter the image width and height in pixels.

3. Choose a DPI value or enter your own.

4. Read the equivalent physical dimensions in millimeters, centimeters, and inches.

5. Use the comparison table to see how the image scales at common DPI values.