How to make a PDF smaller for email

To make a PDF smaller, reduce the weight of its images. Files made of text are already compact, but scans and photo-heavy documents can shrink dramatically when their pictures are compressed.

Nearly every large PDF is large because of images: scanned pages, photos, or high-resolution graphics. A 40-page text report may be 200 KB. The same report scanned at high quality can be 40 MB.

Start with the Gentle level in “Make it smaller”. It tidies the file structure and keeps text selectable. If the file is still too large, try Balanced, then Strong.

Balanced, Strong and Tiny turn each page into a compressed picture. That works well for scans, but the text is no longer selectable, so keep your original.

Many mail services cap attachments around 20 to 25 MB, and some upload forms accept far less. Check the limit first, then compress only as much as you need. Smaller than necessary just costs sharpness.

A PDF that is mostly text may barely change. In that case the tool tells you the file is already well packed and returns the smallest version it found, rather than making it bigger.