How to compress a PDF for email
Updated 30 September 2026
Tool for this guide: Compress PDF
Short answer: most email services cap attachments at 20 to 25 MB, and many work inboxes allow less. Open compress PDF, start with the Recommended level, and switch to Strong only if it's still too big.
Attachment limits
| Email service | Limit per email |
|---|---|
| Gmail | 25 MB |
| Outlook.com | 20 MB |
| Yahoo Mail | 25 MB |
| Company email (Exchange) | Often 10 to 20 MB, set by your IT team |
The limit counts all attachments together, and files grow by about a third when they're attached, so a 20 MB PDF may already fail on a 25 MB limit. Aim for under 15 MB to be safe.
What makes a PDF big?
Almost always it's images: scanned pages, photos and screenshots. Text itself is tiny. That's why a 10-page scan can be 30 MB while a 100-page report is 1 MB.
Choose the right level
| Level | What it does | Text stays selectable | Typical saving |
|---|---|---|---|
| Light | Cleans up and recompresses what it can | Yes | Small |
| Recommended | Shrinks images inside the PDF | Yes | Medium |
| Strong | Turns each page into an optimised image | No | Large |
Use Strong for scans and forms you only need to read or print. Keep Light or Recommended when people need to search or copy the text.
Step by step
- Open compress PDF and add the file.
- Pick a level, or set a target size in KB for upload forms such as compress PDF to 100 KB.
- Download it and check that small print is still readable.
The PDF is processed in your browser and isn't uploaded.
Still too big?
- Split the PDF and send it in two emails.
- Remove pages you don't need, then merge only what matters.
- Send a link from cloud storage for very large files.
Try it now
Make a PDF smaller. Keep text selectable with light compression, or turn pages into optimised images for much bigger savings.
Open compress pdf