The problem: email attachment limits
You have finished a report, a contract, or a presentation, exported it as a PDF, and now you are trying to send it by email. But the file is 35 MB, and Gmail bounces it with a "file too large" error. Outlook is not any better. This is one of the most common small frustrations in office work, and it happens because PDFs with embedded images, charts, or scanned pages are often far larger than they need to be.
The attachment limits for popular email services are:
- Gmail — 25 MB
- Outlook (desktop) — 20 MB
- Outlook.com / Hotmail — 20 MB
- Yahoo Mail — 25 MB
- Apple Mail (iCloud) — 20 MB
Most PDFs can be compressed by 50 to 80 percent without any visible change on screen. A 35 MB report becomes 7 MB. A 20 MB presentation becomes 4 MB. Text stays perfectly sharp because it is stored as vector data and is unaffected by compression.
How to compress your PDF for email
- Open Filero's Compress PDF tool.
- Upload the PDF that is too large to email.
- Select the Balanced preset (150 DPI). This gives the best trade-off between file size and visual quality for email attachments.
- Click Compress and wait a few seconds.
- Check the new file size shown on screen. If it is under 25 MB (or 20 MB for Outlook), download it and attach it to your email.
Which preset should I use?
For email attachments, start with Balanced (150 DPI). This reduces file size by 50 to 70 percent and the document looks identical on screen. If the file is still too large, try Small (72 DPI) for maximum compression (70 to 85 percent reduction). Only use High Quality (300 DPI) if the recipient needs to print the document at professional quality.
What if it is still too large?
If your PDF is still over the email limit after compression with the Small preset, you have two options:
- Split the PDF into smaller sections using Split PDF and send them as separate attachments. You can tell the recipient to merge them back together if they need a single file.
- Use a cloud link instead. Upload the file to Google Drive, OneDrive, or Dropbox and share the link in your email. This bypasses attachment limits entirely.
Frequently asked questions
What is the maximum email attachment size for Gmail and Outlook?
Gmail allows attachments up to 25 MB. Microsoft Outlook (the desktop app) allows up to 20 MB by default. Outlook.com (Hotmail) allows 20 MB. Yahoo Mail allows 25 MB. If your PDF is larger than these limits, compressing it with Filero will usually bring it within range.
Will the recipient notice the PDF has been compressed?
No. With the Balanced preset (150 DPI), the document looks identical on screen and prints well for everyday purposes. Text is never affected by compression because it is stored as vector data. Only embedded images are downsampled, and at 150 DPI the difference is not visible on a computer screen.
What if my PDF is still too large after compression?
Try the Small preset (72 DPI) for maximum compression. If the file is still too large, you can split it into smaller parts using the Split PDF tool and send them as separate attachments, or use a cloud sharing link instead.
Is my PDF kept private during compression?
Yes. Your file is uploaded over HTTPS, compressed on our server using Ghostscript, and deleted immediately after you download the result. It is never stored, shared, or accessed by anyone.