10 Tips to Reduce PDF File Size Before Sending

Whether you're sending an email attachment, uploading to a government portal, or sharing via WhatsApp, file size matters. Here are 10 practical tips to get your PDF under any size limit.

1. Use a browser-based compression tool

The fastest way to reduce file size is a dedicated compression tool. PDFTools Compress re-renders your PDF pages as optimized images and reassembles them — no upload required.

2. Choose the right compression level

For text-heavy documents (contracts, reports), use Low or Medium compression to maintain readability. For scanned photos or image-heavy PDFs, High compression works well.

3. Reduce image resolution before creating the PDF

If you're creating a PDF from scratch, resize images to 150 DPI for on-screen use or 300 DPI for print, rather than leaving them at the original camera resolution.

4. Avoid scanning at unnecessarily high DPI

When scanning physical documents, 150 DPI is sufficient for most purposes. Scanning at 600 DPI creates files 4x larger than 300 DPI with no practical benefit for text documents.

5. Remove unnecessary pages

Use a split tool to extract only the pages you need before compressing. Fewer pages means smaller file.

6. Don't embed unused fonts

If you're creating PDFs programmatically, ensure font subsetting is enabled — this embeds only the characters actually used rather than the entire font file.

7. Convert to grayscale if colour isn't needed

Black-and-white PDFs are significantly smaller than colour ones. If your document has no colour-critical content, consider converting to grayscale.

8. Use PDF/A for archives, not for sharing

PDF/A format embeds all resources for long-term archiving, which makes files larger. Use standard PDF for sharing.

9. Remove metadata and revision history

PDFs that have been edited multiple times accumulate revision history. Re-exporting from a tool that doesn't preserve this metadata can reduce size.

10. Split before sending if needed

If you must share a large PDF and compression isn't enough, split it into parts and send each separately. Most email clients accept multiple attachments.

With these tips and the free tools at PDFTools, you should be able to get any PDF down to a shareable size in under a minute.