Compute screen density specifications with our free DPI Calculator. Calculate Pixels Per Inch (PPI), physical dot pitch (mm), total megapixels (MP), and human visual acuity Retina viewing distances directly inside your browser with complete privacy.
Input display width and height pixels (e.g. 1920 x 1080).
Enter physical screen diagonal measurement in inches (e.g. 15.6).
View instant calculations for PPI density, dot pitch, megapixels, and Retina distance.
Uses the Pythagorean theorem \(\text{PPI} = \sqrt{w^2 + h^2} / d\) to calculate exact pixel density.
Derives optimal distance where human eyes cannot distinguish individual subpixels (1 arcminute acuity).
All calculations execute in local browser memory. Zero display inputs leave your device.
Screen Pixel Density (\(\text{PPI}\)) is computed by calculating the diagonal pixel count via the Pythagorean theorem \(d_p = \sqrt{w^2 + h^2}\) and dividing by the physical screen diagonal in inches: \(\text{PPI} = d_p / d_i\).
Dot pitch represents the subpixel millimeter spacing: \(\text{Dot Pitch (mm)} = 25.4 / \text{PPI}\). Smaller values deliver crisp, high-resolution rendering.
Retina threshold distance utilizes human 20/20 visual acuity (1 arcminute resolution) formula \(\text{Distance (inches)} = 3438 / \text{PPI}\), calculating the exact distance at which individual pixels blend into a continuous image.