How to make a scanned PDF smaller for email and upload limits

Why scanned PDFs are large

A scanned page is a photo, not text. A modern phone camera captures every page at very high resolution, and a ten-page document is ten high-resolution photos inside one file. That is great for detail, and far more than an email or an upload form needs.

Common limits

• Many email services refuse attachments over about 20 to 25 MB in total.
• Online application forms often allow only 1, 2 or 5 MB per file.
• Messaging apps may compress or reject large documents.

1. Choose a smaller size when you save

The easiest fix is to pick a smaller size when you export, instead of shrinking the file afterwards. For most documents, a balanced or email size keeps text perfectly readable at a fraction of the original size.

2. Use Gray or B&W for text

A colour scan of a black-and-white letter carries colour information nobody needs. A grayscale or black-and-white filter makes text pages much smaller and often easier to read.

3. Remove pages that are not needed

Blank backs of pages and duplicate shots add size without adding anything. Remove them before you save.

4. Split one big file into two

If a form allows several uploads but limits each one, splitting a long document into parts, for example the application and its attachments, can be better than squeezing everything into one file.

5. Check the result

After shrinking, open the PDF and zoom in on the smallest text, such as a signature line or a reference number. If it is still sharp, the file is ready to send.

Doing this in Keepscan

When you save or share in Keepscan, choose Original, Balanced or Email size, with free PDFs and no watermark. Keepscan Pro adds “Exactly under a size”, for forms that ask for a file under, say, 2 MB (you can try it once for free), as well as compressing, merging and splitting PDFs. See also how to scan documents into a clean PDF.