Alyvero PDF guide
Compress a PDF for email
Email services can impose attachment limits, and a PDF that looks small on your screen can still be too large to send. Compressing a copy is often the quickest first step.
Practical workflow
Use the attachment limit of your email service as the target rather than chasing an arbitrary percentage reduction.
Alyvero creates a separate result, so you can compare it with the original before deciding which copy to send.
Leave some room below the attachment limit when practical, especially if the service applies a strict maximum.
Check the compressed document before attaching it, particularly when it contains forms, signatures or small print.
How small does the PDF need to be?
There is no universal target. The useful target is the attachment limit of the email service and the amount of room you want below it.
If the limit is 25 MB and your PDF is 24 MB, a tiny reduction technically works but leaves little margin. A file several times larger than the limit may need deeper compression.
Keep readability in mind
A smaller file is not automatically a better file. Text should remain legible, pages should render correctly, and important images should still contain enough detail for their purpose.
Always open the compressed copy before attaching it. Keep the original until you have confirmed the smaller version is acceptable.
If the PDF is still too large
Image-heavy PDFs are a common difficult case. A browser-only optimizer may have limited room to reduce them because the bulk of the bytes are already inside page images.
If that happens, export or scan the source at a more appropriate resolution, or use a tool that explicitly supports image recompression.
Related PDF tools
More PDF help
Explore Alyvero
Use Alyvero's Compress PDF tool when you need a smaller copy for an email attachment. Compare the resulting file size before sending it.
For image-format questions, visit the image tools hub. The PDF and image glossary explains common file terms.