Screen Size and PPI Calculator for Monitors, TVs and Phones
Calculate screen width, height and pixel density from resolution and diagonal size. Everything runs locally in your browser.
How to calculate screen dimensions and pixels per inch
Enter the native horizontal and vertical resolution, then add the advertised diagonal size in inches. The calculator uses the pixel diagonal to estimate PPI and the aspect ratio to find the physical width and height. Use the native panel resolution rather than a scaled desktop setting for the most accurate result.
How to use a screen size and PPI result
PPI is useful for comparing text sharpness between displays, but it does not describe brightness, contrast or color quality. A laptop may report a scaled viewport while the panel still has a higher native pixel count. Check the product specification and operating-system display settings together before choosing a replacement panel or scaling level.
Privacy and accuracy
The calculation runs in your browser and does not upload the dimensions you enter. Results are estimates based on the values supplied, so treat them as planning guidance and verify the manufacturer's specification before making a purchase or calibration decision.