What Is DPI vs PPI?
DPI and PPI are often confused, but they serve different purposes. PPI measures screen density, while DPI is used for print output.
Key Dimensions and Reference Table
| Term | Definition | Typical Use | Common Values |
|---|---|---|---|
| PPI | Pixels per inch | Screens | 72-300 |
| DPI | Dots per inch | Printers | 300-600 |
| Pixel dimensions | Image size | Web and print | 800-4000px |
| Print size | Physical output | Print workflows | 4x6, 8x10 |
Why PPI Matters
PPI defines how sharp an image appears on screens. Higher PPI means more pixels in a smaller space, which looks crisper.
For web images, PPI is less important than pixel dimensions, since browsers render based on pixels.
Why DPI Matters
DPI controls how printers place ink on paper. Higher DPI produces more detailed prints.
When preparing print files, choose the final print size and target 300 DPI for quality.
How to Choose Correct Settings
Start with the output destination. If the image is for web, focus on pixels. If for print, calculate pixel dimensions based on the physical size and DPI.
Use resizing tools to adjust dimensions without distorting the aspect ratio.
Practical Examples
A 3000 x 2000 image at 300 DPI prints at 10 x 6.7 inches. The same image on a website could be resized to 1200 x 800 without visible loss.
Common Mistakes
- Changing DPI without adjusting pixel dimensions.
- Using low DPI for print and getting soft output.
- Confusing PPI settings with actual image size.
Related Guides
image resolution explained, aspect ratio explained, resize without losing quality. Return to the PixelPerfect Resizer homepage to resize your images.
FAQ
What is the difference between DPI and PPI?
PPI is for screen density, DPI is for print output.
Does PPI affect web images?
Not much. Pixel dimensions are what matter for web display.
What DPI should I use for print?
300 DPI is the standard for high-quality prints.
Can I change DPI without resizing?
Yes, but it will not change the actual pixel dimensions.
Why does DPI matter for posters?
Large prints need enough DPI to stay sharp at close range.
Is 72 DPI too low?
For print, yes. For web, DPI is less relevant.
How do I calculate print size?
Divide pixel dimensions by DPI to get inches.
Where can I resize for print?
Use PixelPerfect Resizer to adjust dimensions precisely.