EmailGmailOutlookHow-To⏱ 4 min read
How to Compress PDF for Email Attachment — Gmail and Outlook (2025)
Email platforms have strict file size limits for attachments. If your PDF is too large to send via Gmail or Outlook, compressing it first is the fastest solution and it takes less than a minute.
Email Attachment Size Limits
Attachment Limits by Platform
- Gmail: 25MB per email
- Outlook.com: 20MB per email
- Yahoo Mail: 25MB per email
- Corporate email servers: Often as low as 5-10MB
How to Compress PDF for Email
1
Open ShrinkPDF.com
Visit ShrinkPDF.com in your browser. Works on Mac, Windows, iPhone, and Android.
2
Upload Your PDF
Drag and drop or click to upload. No file size restrictions.
3
Choose Balanced Compression
For email, Balanced reduces size by 40-60% while keeping quality high enough for any document.
4
Download the Compressed PDF
The whole process takes under 10 seconds for most files.
5
Attach to Your Email
Attach the newly compressed PDF to your email as usual. Smaller file means faster sending.
What if the File is Still Too Large?
- Use Google Drive or OneDrive — upload the file and share a link instead
- Try WeTransfer.com — free for files up to 2GB
- Use Maximum compression on ShrinkPDF and try again
- Split the PDF into multiple smaller files and send separately
✓ Try ShrinkPDF Free — No Login Required
No registration. No file size limit. Your file never leaves your browser.
📚 Compress My PDF Now
Frequently Asked Questions
Will the recipient notice any quality difference? ▼
For text-heavy documents like contracts, reports, or invoices, quality is essentially identical. For image-heavy PDFs, Balanced compression is virtually unnoticeable.
Can I compress a PDF that already has a digital signature? ▼
Yes. Compression typically preserves digital signatures. However, for highly sensitive legal documents, verify the signature is intact after compression.
How small can a 10MB PDF get? ▼
A typical 10MB text-heavy PDF can compress to 3-5MB on Balanced, or 1-2MB on Maximum. Image-heavy PDFs vary more depending on content.