Pixel Density Converter Free Online
Convert pixel density between PPI (pixels per inch), DPI (dots per inch), dots per mm, and pixels per cm. PPI describes screens; DPI describes printers — same numerical scale, different concepts.
All Units
Pro — bulk batch conversion, API access, history & favorites
API access · Priority queue · Team workspace
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How It Works
Pick Your Unit or Preset
Choose your home unit using the dropdown or load a one-click preset. Defaults are sensible engineering values so you can start right away.
Enter a Value
Type a number — conversion runs as you type. Many tools have multiple input boxes (W & H, size & speed) — edit any of them and the rest recompute.
Read Every Equivalent
Below the main result, the All Units / Summary panel shows your value across every supported unit, with engineering context (FPS, ping, EM band, etc.) where relevant.
Pixel Density Converter Features
Screens (PPI)
PPI describes display density. iPhone 15 Pro = 460 PPI. iMac 27" 5K = 218 PPI. A 1080p 24" monitor = ~92 PPI.
Printing (DPI)
DPI is the printing standard. 300 DPI is the minimum for sharp magazine print; 600 DPI for fine line art; 1200+ DPI for professional photography.
Dot Pitch
The inverse — how big each pixel is in mm. Dot pitch 0.25 mm = 102 PPI. Smaller dot pitch = sharper image.
Metric & Imperial
PPI/DPI use inches; ppcm/ppmm use the metric scale. 300 DPI = 11.81 ppmm = 118.1 ppcm.
Live Conversion
Type a value, see all units instantly.
100% Private
All math runs in your browser.
Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| Full pixel density conversion | ||
| Live conversion | ||
| All-units result panel | ||
| Bulk CSV / Excel conversion | — | |
| REST API access | — | |
| Custom precision settings | — |
Frequently Asked Questions
Numerically yes — both use inches. Conceptually different: PPI is for digital displays (square pixels on screen), DPI is for printing (round dots of ink). 300 PPI photo = 300 DPI on a 1:1 print.
Standard quality: 300 DPI. Newspaper/draft: 150 DPI. Fine art / photo book: 360–600 DPI. Billboards (viewed far away): 30–100 DPI is fine.
The physical distance between adjacent pixel centers, in mm. 0.25 mm dot pitch = 25.4/0.25 = 101.6 PPI. Lower dot pitch = sharper screen.
iPhone 15 Pro packs 460 PPI in a 6.1-inch panel. The human eye stops resolving individual pixels at ~300 PPI at 12 inches viewing distance — Apple calls anything above this Retina.
Because of pixel density. A 32" 4K = 138 PPI; a 32" 1080p = 69 PPI. If your screen is large enough that 4K only doubles to ~140 PPI, the difference is noticeable but not huge unless you sit close.