ClarityHow to use this tool
- Enter horizontal pixels, vertical pixels, screen diagonal (inches).
- Select Calculate to view the result.
- Check the method and assumptions below before using the result.
Input reference and sample values
Use the units and choices shown for each field. Sample values are provided for practice, not as recommendations.
| Input | Format and units | Sample |
|---|---|---|
| Horizontal pixels | Numeric value. Minimum: 1. Maximum: 100000. | 1920 |
| Vertical pixels | Numeric value. Minimum: 1. Maximum: 100000. | 1080 |
| Screen diagonal (inches) | Numeric value. Minimum: 0.01. Maximum: 10000. | 24 |
Result for these sample inputs
91.7877988 pixels/inch
- Screen width (inches)
- 20.9178129
- Screen height (inches)
- 11.7662698
- Pixel pitch (mm)
- 0.276725233
Select Try the example in the form to load these values and calculate them again. This replaces the current form inputs. Compare the result with the method and worked explanation below.
The method, explained
PPI = square root of (horizontal pixels² + vertical pixels²) ÷ diagonal inches. Physical width = horizontal pixels ÷ PPI. Pixel pitch = 25.4 ÷ PPI millimeters.
A 1920 × 1080 screen with a 24-inch diagonal has approximately 91.79 PPI and is 20.92 inches wide.
What to keep in mind
Assumes square pixels and an accurately measured active-screen diagonal, excluding bezels. PPI alone does not measure perceived sharpness, viewing distance, color quality or software scaling.
Common questions
Is screen PPI the same as printer DPI?
No. Screen PPI counts pixels per inch; printer DPI describes ink-dot placement and is a different specification.
Does changing operating-system scaling change physical PPI?
No. Scaling changes interface size, not the physical pixel spacing.
Methodology maintained by ClarityKit. How these tools are built and checked.