You've finished your report, saved it as a PDF, and gone to attach it to an email — only to see the dreaded message: "File exceeds maximum attachment size." Gmail limits attachments to 25MB. Outlook is set to 20MB by default. Yahoo Mail caps at 25MB. And many corporate email systems have even stricter limits.
Here's how to compress your PDF so it fits within email attachment limits without compromising the document's readability.
As a general rule:
For professional communications, aim for under 5MB. For a simple CV or report, under 2MB is ideal.
The quickest solution is using a free online compressor. The process takes under 60 seconds:
Files processed in your browser. No upload, no signup, instant results.
Compress PDF Now →The right compression level depends on your PDF's content and how important visual quality is:
This is the sweet spot for most email attachments. Text remains crisp and readable, images are noticeably compressed but still clear. A 10MB PDF typically becomes 4-5MB — well within most email limits.
Use this when you absolutely must hit a specific file size target. A 20MB scanned document can often be compressed to under 3MB. Image quality is reduced but text remains fully readable. Best for documents that will be viewed on screen, not printed.
Important: Text-only PDFs (like simple reports or forms) won't compress as dramatically as image-heavy ones. A 1MB all-text PDF might only reduce to 800KB even on Maximum setting — because the text is already stored efficiently.
If you have access to the original document (Word, PowerPoint, etc.), re-exporting with different settings often produces a smaller PDF than compressing an already-exported one:
Go to File → Save As → PDF. In the dialog, look for an "Options" or "Optimize for" setting. Select "Minimum size (publishing online)" instead of "Standard." This can reduce file size by 50-70%.
Go to File → Download → PDF Document. Google's PDF export is already reasonably optimised. If the file is still too large, run it through a PDF compressor afterwards.
If the PDF is too large to compress sufficiently while maintaining acceptable quality, consider sharing it via a cloud link instead:
This is especially useful for portfolios, large presentations, or documents with many high-quality images where compression would unacceptably reduce quality.
After compressing, always check the file size before attaching:
If the compressed file is still too large, try Maximum compression or consider splitting the document into multiple smaller PDFs.
For most email attachment issues, a free online PDF compressor solves the problem in under a minute. Choose Balanced compression for a good quality-to-size ratio, or Maximum compression when you need to hit a specific small file size.
If the PDF contains sensitive information, use a tool that processes files locally in your browser — your document should never need to travel to a third-party server just to be compressed.