Compress PDF for Email
The email bounced or the attachment won't send. Here's the fastest fix — and the size limits you need to know for each major email provider.
Email attachment size limits by provider
| Provider | Attachment limit | Over limit |
|---|---|---|
| Gmail | 25 MB | Offers to send via Drive link |
| Outlook (personal) | 20 MB | Email bounces or is blocked |
| Outlook (work/Exchange) | 10 MB typical | Set by IT admin — varies |
| Yahoo Mail | 25 MB | Upload fails at compose screen |
| Apple Mail (iCloud) | 20 MB | iCloud Mail Drop for larger files |
The fastest way to compress a PDF for email
Open this PDF compressor, drop your file in, and pick Balanced compression. That's the right default for email: it reduces most PDFs by 40–60% while keeping text sharp and images readable on any screen. The download takes a few seconds.
If Balanced doesn't get you under the limit, try Maximum. A 20 MB scanned report typically compresses to 4–7 MB on Maximum — well under any provider's limit.
When the PDF is still too large
Some PDFs — particularly high-resolution architectural drawings, print-ready brochures, or CAD exports — are genuinely too large to send as attachments even after compression. Your options:
- Share via cloud link: Upload to Google Drive, OneDrive, or Dropbox and paste the link into your email. The recipient doesn't need an account to download.
- Split the PDF: Use a PDF splitter to break it into parts and send in two emails.
- Remove unnecessary pages: A page remover lets you strip pages the recipient doesn't need before compressing.
What about corporate email filters
Corporate mail servers sometimes block or quarantine PDFs over a certain size, even if they're technically under the provider's stated limit. The threshold varies, but 10 MB is a common internal limit. If someone in an office says they didn't receive your attachment, try compressing to under 8 MB and resending.
Some servers also flag PDFs that contain unusual metadata or large embedded JavaScript. If your compressed PDF still gets blocked, try using the merge tool to re-export it cleanly, which strips non-essential data.
Get your PDF under the email limit
Choose Balanced for most emails. Takes under a minute.
Frequently asked questions
What is the maximum attachment size for Gmail?
Gmail allows attachments up to 25 MB. If your file is larger, Gmail will automatically offer to send it via Google Drive instead. The recipient gets a link rather than a direct attachment.
What is Outlook's attachment limit?
Microsoft Outlook (personal accounts) limits attachments to 20 MB. Exchange/Office 365 accounts managed by an IT department may have a lower limit — commonly 10 MB — set by the administrator.
My PDF is 8 MB and the limit is 10 MB — should I still compress it?
It's worth it. A compressed version at Balanced quality is typically half the size, which makes it faster for the recipient to download and reduces the chance it gets blocked by strict spam filters that flag large attachments.
Will compressing make the PDF unreadable on mobile?
No. The Balanced compression level renders pages at ~144 DPI — more than sufficient for reading on a phone screen. Text stays sharp and images stay clear. Only use Maximum compression if the recipient only needs to skim the document.
What if the PDF is still too large after compressing?
Try Maximum compression first. If that's not enough, consider splitting the PDF into smaller parts and sending them in separate emails, or share it via a cloud link (Google Drive, OneDrive, Dropbox) and paste the link into your email.
Does compressing change the file content?
The text and images remain the same — compression only changes the resolution and encoding of images within the file. The document looks the same to the reader, just with slightly lower image sharpness at very high zoom levels.