Resolution: DPI vs PPI
DPI (dots per inch) and PPI (pixels per inch) describe how densely pixels are packed in an image. While often used interchangeably, they refer to different stages — PPI for digital images, DPI for printer output.
Web images typically use 72-96 PPI. Screens display one pixel per pixel, so higher density doesn’t improve quality. A 1000-pixel-wide image displays at 1000 pixels regardless of its PPI setting.
Print images require 300 PPI for professional quality. At 300 PPI, a 3000x2400 pixel image prints at 10x8 inches. The same image at 72 PPI would print at 41.7x33.3 inches but look pixelated and blurry.
The relationship is simple: print size = pixels / PPI. Understanding this prevents ordering prints that look nothing like what you expected.
Color Modes
RGB (Red, Green, Blue) is used for screens and digital display. It produces bright, vibrant colors by combining light. All web images use RGB.
CMYK (Cyan, Magenta, Yellow, Key/Black) is used for printing. It creates colors by subtracting light from white paper. The CMYK color gamut is smaller than RGB, so some bright screen colors cannot be reproduced in print.
When preparing images for print, convert from RGB to CMYK using professional software. This prevents color surprises when the printed output looks duller than the screen version.
File Format Differences
Web formats:
- JPG: Small files, universal support, ideal for photos
- PNG: Transparency, lossless quality, ideal for graphics
- WebP: Modern alternative with superior compression
- SVG: Scalable vector graphics for logos and icons
Print formats:
- TIFF: Lossless, high quality, widely supported by printers
- High-resolution PDF: Embedded images at print quality
- EPS: Vector format for logos and illustrations
- PSD: Native Photoshop format preserving layers
Dimension Calculations
Common print sizes at 300 DPI:
| Print Size | Pixels at 300 DPI |
|---|---|
| 4x6 inches | 1200x1800 |
| 5x7 inches | 1500x2100 |
| 8x10 inches | 2400x3000 |
| 11x14 inches | 3300x4200 |
| A4 (8.3x11.7) | 2480x3508 |
Use our resize tool to prepare images at exact pixel dimensions for your target print size. Simply calculate pixels = inches × 300, then resize accordingly.
Workflow Tips
Start with the highest resolution available. You can always downsize for web, but you cannot create detail that doesn’t exist.
Save web and print versions separately. Web versions should be compressed and sized appropriately. Print versions should remain at full resolution in lossless formats.
Include metadata and color profiles. ICC color profiles help ensure consistent color reproduction across different devices and printers.
Never use a web-optimized image for print. The compression, low resolution, and RGB color mode will produce poor results. Always maintain separate optimized versions for each use case.