PDF File Size
Why Is My PDF So Large?
Large PDFs are usually caused by high-resolution images, scans or document resources that were not optimized.
High-resolution scanned pages
A scanner may store each page as a large image. Multiplying that image data across dozens or hundreds of pages can create a very large PDF.
Photographs and color graphics
Photos contain much more visual information than plain text. A PDF with several full-resolution photos can grow quickly.
Embedded fonts and duplicated resources
PDFs can include embedded font data, repeated images and other internal resources. Some creation tools optimize these well; others leave redundant data.
How to make the file smaller
Try structural compression first. If the document is a scan and remains too large, a future scan at a lower appropriate resolution may create a better source file. Splitting can also help when only part of the document needs to be shared.