DPI vs PPI: What Is the Difference and Why It Matters
Parth Soni
Editorial Team
Key Takeaway
“Demystifying digital resolution. Understand when to use Dots Per Inch (DPI) for print and Pixels Per Inch (PPI) for screens to ensure perfect clarity.”
It is one of the most common questions in digital imaging: "Can you make this logo 300 DPI?". But what does that actually mean? And why does a 300 DPI image sometimes look pixelated, while a 72 DPI image looks sharp? Let's demystify the acronyms.
The Core Abbreviations
PPI
Pixels Per Inch
For Screens. This measures the density of glowing squares (pixels) on a digital display. It controls the quality of the image on the monitor, phone, or tablet.
DPI
Dots Per Inch
For Printers. This measures the density of physical ink dots a printer sprays onto paper. Printers use CMYK dots to simulate colors, requiring varying densities.
The "72 DPI" Myth
For decades, the standard for web images was 72 PPI. This originated from the original Apple Macintosh screens in the 1980s.
Here is the truth: Modern screens are much denser. A standard laptop is around 120-140 PPI. An iPhone "Retina" display is 460+ PPI.
Crucial Concept
Browsers ignore metadata DPI. If you upload a 1000px wide image to a website, the browser displays 1000 pixels. It does not care if the file says "72 DPI" or "3000 DPI". The metadata is irrelevant for web display.
When DPI Matters: The Print Equation
Physical size (Inches) and Digital Size (Pixels) are linked by DPI. The formula is simple:
Let's say you want to print a 4 x 6 inch photo.
- Low Quality
Printing at 72 DPI
4" × 72 = 288 pixels.
Result: Blurry, blocky print. Looks like "Minecraft". - High Quality
Printing at 300 DPI
4" × 300 = 1200 pixels.
Result: Crisp, professional photo. Standard for magazines.
How to Change DPI/PPI
Note: Increasing the DPI setting in metadata without adding more pixels (resampling) will simply make the print size smaller. To print large AND high quality, you need a high-resolution source image.
Using Photoshop
Image > Image Size. Uncheck "Resample" to see the physical size change as you adjust DPI. Check "Resample" to actually add pixels.
Parth Soni
Content Specialist
Expert contributor at Editobox, specializing in digital document processing and image optimization.
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