DPI/PPI Calculator

How to Use the DPI/PPI Calculator

Our DPI/PPI calculator offers three powerful modes to help you work with pixel density, print dimensions, and viewing distances. Each mode is designed for specific professional needs.

Calculate Screen PPI (Pixels Per Inch)

To determine your screen's pixel density, enter the resolution width and height in pixels, then provide the diagonal screen size in inches. The calculator instantly computes the PPI and tells you whether your display qualifies as a Retina display.

Practical applications: Compare monitors before purchasing, understand image sharpness on different devices, determine if a display is suitable for photo editing or graphic design work.

Calculate Print Dimensions from Image Resolution

When preparing images for print, enter your image dimensions in pixels and the desired print DPI (typically 300 for high-quality prints). The calculator shows the maximum print size in inches, centimeters, and millimeters.

Professional use cases: Determine if your photo has enough resolution for a poster print, calculate canvas sizes for wall art, prepare images for professional printing services.

Calculate Optimal Viewing Distance

Enter your screen's diagonal size and PPI to find the ideal viewing distance. This calculation is based on the ability of the human eye to distinguish individual pixels at different distances.

Useful for: Setting up home theaters, positioning desktop monitors ergonomically, planning digital signage installations, optimizing presentation displays.

Understanding Retina Displays

Apple's "Retina" designation refers to displays where individual pixels are imperceptible at normal viewing distances. The threshold varies by device: iPhones need 300+ PPI (held at 10-12 inches), while MacBooks need 220+ PPI (viewed at 20-24 inches). Our calculator automatically determines if a display meets Retina standards based on typical viewing distances.

DPI Standards for Different Print Types

High-quality photos: 300 DPI is the professional standard for photo prints, ensuring sharp detail and smooth color gradients.

Large format prints: 150-200 DPI works well for posters and banners viewed from a distance, as the viewing distance reduces the need for higher density.

Billboards and signage: 20-50 DPI is sufficient for large outdoor displays meant to be viewed from far away.

Web images: 72-96 DPI is the standard for digital displays, as monitors have fixed pixel densities regardless of image DPI settings.

Comparing Popular Display Densities

Modern smartphones lead in pixel density, with flagship devices reaching 400-500 PPI. High-end tablets typically offer 250-300 PPI, providing sharp text and images for reading and creative work. Desktop monitors range from 90 PPI (large 4K displays) to 220 PPI (Apple Retina displays), with 100-150 PPI being most common for standard monitors.

How PPI Affects Image Quality

Higher PPI displays show more detail and produce sharper images, but there are practical limits. Beyond certain thresholds (around 300 PPI for smartphones, 220 PPI for laptops), improvements become difficult to perceive. The optimal PPI depends on viewing distance - displays viewed from further away can have lower PPI while maintaining perceived sharpness.

Preparing Images for Different Outputs

When creating content, always consider the final output. For screen display, image dimensions in pixels matter more than DPI settings. For print, ensure your image has enough pixels to achieve the desired physical size at 300 DPI. Use our calculator to verify your images meet resolution requirements before sending files to print.