1. Check the Recipient’s Attachment Limit
Business email limits vary by organization and service. The total message size can differ from the attachment’s size on disk. Leave room for other attachments and the message itself.
2. Match Compression to the Document
A text-only PDF that is already optimized may shrink very little. Large scans and photos benefit more from adjusting image resolution and quality. The web tool offers structural compression; image reduction options are in the Windows application.
3. Try a Target Size in the Windows Application
Open Reduce / Compress PDF. Start with Balanced. Choose For Email for a smaller file and, if needed, enter a target such as 3 MB. Try grayscale only when colour is not important to stamps, marks or charts.
4. Check Small Text and Critical Details
Zoom in on account numbers, dates, small-print terms and signature images. If scanned text looks too soft, use higher quality. Keep the original separately. Re-saving a digitally signed document can affect its signature, so do not replace the signed original.
5. Compare the Actual Output Size
Not every file can meet the same MB target. Check the size in the tool and in the downloaded file. If necessary, use your organization’s approved file-sharing method rather than reducing readability too far.
Frequently Asked Questions
Can every 20 MB PDF be reduced to 3 MB?
No. Images, page count and starting quality determine the result. Different documents may require different quality levels to reach the same target.
Is grayscale suitable for every document?
No. Keep colour when charts, stamps or meaningful markings depend on it. Use grayscale only for suitable documents.
Related Tools and Guides
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