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How to Compress a PDF So It's Small Enough to Email

Hit an 'attachment too large' error? PDFs balloon when they contain scanned pages or high-resolution images. Compressing re-encodes those pages at a sensible quality so the file fits common 20–25MB email limits.

  1. 1. Open the compressor

    Go to the Compress PDF tool and drop in your file. Everything runs locally — your document isn't uploaded.

  2. 2. Pick a level

    Start with Balanced. Choose Strong for the smallest file (best for scans), or Light to preserve maximum quality.

  3. 3. Compress and check

    Run it and review the before/after size. If it's still too big, try a stronger level.

  4. 4. Download or share

    Download the smaller PDF, or create a 1-hour share link to send a download instead of an attachment.

Tips

  • Compression flattens pages to images, so selectable text becomes non-selectable — run OCR afterwards if you need it searchable again.
  • If your file is mostly text, it may already be small; a stronger level helps most with image-heavy scans.

Ready to try it?

Open the Compress tool
How to Compress a PDF So It's Small Enough to Email | DocuScan