PPI to DPI Converter
Convert your screen’s pixel density (PPI) into print resolution (DPI) for sharp, high-quality prints.
Understanding PPI and DPI
In the world of digital imaging and printing, PPI and DPI are two important measurements that often get confused:
- PPI (Pixels Per Inch): Refers to the pixel density on a digital display or image file. Higher PPI values mean more detailed, sharper images.
- DPI (Dots Per Inch): Refers to the resolution of a printed image. It measures how many ink dots a printer places within one inch of paper.
While they are technically different, converting between them is necessary when preparing digital images for printing, since you need to ensure your screen resolution translates to high-quality print output.
Formula for Conversion
DPI = PPI × (Scale Factor ÷ 100)
The scale factor allows you to resize images before printing. For example, if you scale an image to 200% of its original size, the effective DPI is halved.
Recommended DPI for Printing
Different types of print jobs require different DPI values:
| Print Type | Recommended DPI |
|---|---|
| Large Posters / Banners | 75–150 DPI |
| Everyday Office Printing | 150–200 DPI |
| Magazines / Brochures | 200–300 DPI |
| Professional Photo Printing | 300–600 DPI |
| Fine Art Prints | 600+ DPI |
Example Calculation
Suppose you have an image at 300 PPI and you print it at 150% of its original size:
DPI = 300 × (100 ÷ 150) = 200 DPI
This falls within the acceptable range for high-quality office printing, but might not be enough for professional photography.
Common Mistakes to Avoid
- Confusing PPI and DPI: PPI relates to the image, while DPI relates to the printer output.
- Printing Low-PPI Images: Even if your printer supports 600 DPI, a 72 PPI image won’t look sharp.
- Ignoring Scale Factor: Enlarging images reduces effective DPI, making prints appear blurry.
FAQs
Is 300 DPI always necessary?
No. While 300 DPI is a good standard for photos, large posters often look fine at 150 DPI since they are viewed from farther away.
Does higher PPI mean higher DPI?
Not automatically. The relationship depends on the scale factor and how you size the image for print.
Can I increase DPI without losing quality?
No. Increasing DPI artificially doesn’t add detail. You need an image with enough original pixels to support the higher resolution.
Conclusion
Converting PPI to DPI ensures that your digital images maintain the sharpness and detail you expect when printed. Use the calculator above to adjust for scaling and find the right balance between file size, quality, and printing needs.