How to get a PDF under an email size limit

Email providers commonly cap attachments at around 20 to 25 MB, and attachments grow by roughly a third when encoded for sending. A 19 MB PDF can therefore be refused by a 25 MB limit. Check your provider's exact number, then aim well below it.

Find out why the file is large

A PDF made from typed text is usually small. Large ones are almost always scans or photos. A page scanned at 600 dpi holds far more pixels than anyone needs on screen, and a 30-page scan can pass 50 MB.

Steps that work, in order

1. Remove pages you do not need. Use Remove PDF Pages to drop blank pages, covers or duplicates. This costs no quality.
2. Compress scans. Use PDF Compress at about 110 dpi and quality 60. This stays readable for normal text pages.
3. Split if still too big. PDF Split can cut the file into parts to send in separate emails.
4. Use a share link. If the file must stay high quality, upload it to a cloud drive and send the link.

What you lose

Compression here converts pages to images, so you can no longer select or search the text. Fine detail such as small print may blur at low settings. If the recipient needs searchable text, send the original by link instead. Always keep the original file and test the result by zooming in on the smallest text before you send it.

Checking the result

Open the smaller file and zoom to the smallest text, such as footnotes, table figures and stamps. If those are still legible at 100 percent zoom, the settings are safe. If not, raise the quality or resolution one step and try again. Compare the sizes on the download line: if the new file is not clearly smaller than the original, the PDF was probably already efficient and you should split it or send a link instead.

Related: all tools.