1. What is DPI?

DPI (Dots Per Inch) is a measurement of printing or display resolution that indicates how many individual dots can fit within a linear inch. It's an important factor in determining image quality for both digital displays and printed materials.

2. How Does the Calculator Work?

The calculator uses the DPI formula:

Where:

• \( width_{px} \) — Image width in pixels
• \( height_{px} \) — Image height in pixels
• \( diagonal_{in} \) — Screen or print diagonal size in inches

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

3. Importance of DPI Calculation

Details: Knowing the DPI helps ensure images appear at the correct size and quality for their intended use, whether for web display, printing, or professional graphics work.

4. Using the Calculator

Tips: Enter the image dimensions in pixels and the physical diagonal size in inches. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between DPI and PPI?
A: DPI (Dots Per Inch) refers to printer resolution, while PPI (Pixels Per Inch) refers to screen resolution, though the terms are often used interchangeably.

Q2: What is a good DPI for printing?
A: For high-quality prints, 300 DPI is standard. For large format prints viewed from a distance, 150 DPI may be sufficient.

Q3: Does DPI affect file size?
A: DPI itself doesn't affect file size - it's metadata that tells how the image should be printed. Pixel dimensions determine file size.

Q4: How does DPI relate to screen resolution?
A: On screens, higher DPI (or PPI) means sharper images as more pixels are packed into each inch.

Q5: Can I change DPI without resizing?
A: Yes, changing DPI without changing pixel dimensions only affects how the image will print, not its digital display or file size.