1. What is a Pixel Per Inch (PPI) Calculator?

Definition: This calculator measures the pixel density of a screen by calculating how many pixels fit into one linear inch of display.

Purpose: It helps determine screen sharpness and image quality, useful for designers, photographers, and when comparing display devices.

2. How Does the PPI Calculator Work?

The calculator uses the formula:

Where:

• \( PPI \) — Pixels per inch (measure of pixel density)
• \( Width_{pixels} \) — Horizontal resolution in pixels
• \( Height_{pixels} \) — Vertical resolution in pixels
• \( Diagonal \) — Screen size measured diagonally in inches

Explanation: The formula calculates the diagonal resolution in pixels and divides it by the physical screen size in inches.

3. Importance of PPI Calculation

Details: Higher PPI means sharper images and text. Understanding PPI helps in choosing displays for specific needs like graphic design, photography, or general use.

4. Using the Calculator

Tips: Enter the screen's resolution (width and height in pixels) and its diagonal size in inches. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a good PPI for a smartphone?
A: Modern smartphones typically have 300-500 PPI for sharp display. 300+ PPI is generally considered "retina" quality.

Q2: How does PPI differ from DPI?
A: PPI refers to screen pixel density, while DPI (dots per inch) refers to printer resolution. They're often used interchangeably but are different concepts.

Q3: Does PPI affect image quality?
A: Yes, higher PPI displays can show more detail, but the benefit diminishes as PPI increases beyond what the human eye can distinguish at normal viewing distances.

Q4: What's the PPI of a 4K 27-inch monitor?
A: A 3840×2160 (4K UHD) 27" monitor has about 163 PPI.

Q5: How do I find my screen's resolution?
A: On Windows: Settings > System > Display. On Mac: Apple menu > About This Mac > Displays.