When exporting PDF pages to images or scanning documents, choosing the right DPI determines whether your files look crisp or blurry and whether they take up 500KB or 50MB. Here is how the four major DPI tiers compare.
Quick DPI Comparison Table (Standard A4 Page)
| DPI Tier | A4 Pixel Dimensions | Total Megapixels | Avg. File Size (PNG) | Recommended Use |
|---|---|---|---|---|
| 72 DPI | 595 × 842 px | 0.5 MP | 120 KB – 300 KB | Fast web previews, low-bandwidth mobile drafts |
| 150 DPI | 1240 × 1754 px | 2.2 MP | 500 KB – 1.5 MB | Business email sharing, office laser printing |
| 300 DPI | 2480 × 3508 px | 8.7 MP | 2.5 MB – 6.0 MB | Commercial magazines, brochures, accurate OCR |
| 600 DPI | 4960 × 7016 px | 34.8 MP | 10 MB – 25 MB | Archival document scanning, microtext, museum art |
72 DPI – Legacy Web & Draft Screen Display
72 DPI was standard for classic 1980s Macintosh displays. Today, modern Retina and 4K displays feature 200+ PPI, making 72 DPI look pixelated when zoomed.
150 DPI – Standard Office & Email Quality
150 DPI is the industry sweet spot for daily corporate communication. Text is completely readable on all screens and laser printers while keeping file sizes lightweight.
300 DPI – Professional Commercial Print Standard
At 300 DPI, individual dots blend together beyond human eye resolution at standard reading distance (12–15 inches), creating smooth photographic gradients.
600 DPI – Ultra-HD Archival & Legal Scans
600 DPI captures microscopic details such as security watermarks, bank check fibers, and tiny legal footnotes.
Frequently Asked Questions
Which DPI should I choose on PDFRack when converting PDF to image?
Choose 150 DPI for web and email sharing, 300 DPI for high-quality printing and OCR, and 600 DPI for ultra-HD archiving.