Pixels per inch from resolution/size.. PPI/DPI Calculator is a free online tool from the ToolsRift Finance & Health Calculators collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Enter the horizontal and vertical resolution in pixels and the diagonal screen size in inches. The calculator shows the display's pixels per inch.
PPI = √(width² + height²) in pixels / diagonal screen size in inches. It combines the resolution and physical size to measure pixel density.
PPI (pixels per inch) describes screen pixel density, while DPI (dots per inch) refers to print resolution. The terms are often used interchangeably for displays.
Higher PPI means sharper images and text, as individual pixels become harder to see. Small high-resolution screens like phones have very high PPI.