Frequently Asked Questions
What DPI should images be in a PDF?
For PDFs viewed on screen, 150 DPI is sufficient. For PDFs that will be printed, use 300 DPI. Over 300 DPI provides no visible benefit and dramatically increases file size.
Why is my PDF so large?
Large PDFs are almost always caused by uncompressed or oversized images. A single 5000x3000 pixel JPEG can be 15 MB. Compressing images before inserting them into your PDF is the most effective way to reduce size.
What image format is best for PDFs?
JPEG is best for photographs in PDFs — it provides good quality at small file sizes. PNG is better for screenshots, diagrams, and images with text where sharp edges matter.
How do I keep PDF images looking sharp?
Use 150+ DPI, avoid over-compressing (keep JPEG quality above 75%), and don't resize images below their display size in the PDF. Balancing these factors keeps images sharp while managing file size.
