How to Reduce PDF File Size for Email and Upload Limits
Why PDFs get large, how to shrink them for email or form uploads, and what to do when a file still won’t fit.
Short answer
Most oversized PDFs are large because of images: scans, phone photos or high-resolution graphics. Lowering image resolution and JPEG quality is what makes a real difference. Open Compress PDF, choose Strong, and check the reported size against your limit.
Why is my PDF so large?
- Scanned pages are stored as full-page images, often at 300 dpi or more.
- Phone photos converted to PDF keep their full camera resolution (often 3–5 MB each).
- Embedded fonts and graphics add some size, but rarely as much as images.
Step by step
- Check the current size in your file manager.
- Open Compress PDF and choose your file.
- Try Strong — balanced first. It keeps pages readable while cutting image data.
- If the result is still over the limit, try Strong — smallest.
- Open the result and zoom in to confirm small text is still legible.
If it still doesn’t fit
- Split the document with Split PDF and send it in parts.
- Remove pages you don’t need with Delete PDF Pages.
- Rebuild from smaller photos: if you made the PDF from phone photos, resize the photos first and recreate it with JPG to PDF.
Trade-offs to know
Basic compression keeps text selectable but usually saves little. Strong compression turns each page into an image, so text can no longer be searched or copied and links stop working. For contracts or forms that must stay searchable, keep the original and share it through a file link instead.