How to compress a PDF for email on Mac
Most email providers reject messages over about 20 to 25 MB, and a PDF grows by about a third once it’s attached. Aim for a PDF well under 15 MB. On a Mac, right-click the PDF, choose FileMate › Compress PDF, and attach the smaller copy it saves next to the original. If the PDF can’t get small enough, Apple Mail’s Mail Drop can send it as a download link instead.
FileMate compresses the PDF on your Mac before you attach it. Nothing is uploaded to a converter first.
Make a PDF small enough to email
- In Finder, right-click the PDF and choose FileMate › Compress PDF.
- Check the new size in the result. For email, under 10 MB is comfortable almost everywhere.
- Still too big? Choose Stronger, or Maximum for scanned documents.
- Attach Report compressed.pdf to your message.
Email size limits
Attachments are encoded as text for sending, which makes them about 33% larger. A 20 MB PDF becomes a message of roughly 27 MB.
| Provider | Message limit |
|---|---|
| Gmail | 25 MB |
| iCloud Mail | 20 MB, unless Mail Drop is used |
| Outlook.com | 20 MB |
| Company mail servers | Often 10 to 25 MB, set by the organisation |
The recipient’s limit matters as much as yours. A message your provider accepts can still bounce at a company whose server allows only 10 MB. If you don’t know the recipient’s limit, keep attachments under 10 MB in total.
When compression isn’t enough: Mail Drop
Apple Mail can send large attachments with Mail Drop. When a message is too large for your mail server, Mail offers to send the attachment through iCloud. The recipient gets a download link that works for 30 days, and attachments up to 5 GB are allowed.
Mail Drop is useful for files that shouldn’t lose any quality. The trade-off is that the file is stored in iCloud and the recipient has to download it, rather than having the PDF in the email itself.
Compressing in Preview instead
Preview’s File › Export › Quartz Filter › Reduce File Size can make a PDF smaller, with one fixed setting. It works on some documents, blurs scans on others, and can even make an already compressed PDF bigger. You also have to export and name each file yourself.
Several PDFs for one message?
Select them all in Finder and choose FileMate › Compress PDFs. Each one gets its own compressed copy. If the recipient prefers one document, Merge into PDF… combines them into a single PDF in the order you choose, and you can compress that.
Get FileMate
Compress the PDF in Finder, attach the smaller copy, send. FileMate keeps the original as it was and does the work on your Mac.
Normal price €9.99, now €4.99 incl. VAT
One payment, no subscription. macOS 14 Sonoma or later, Apple silicon or Intel.