How to Reduce PDF File Size for Online Forms and Email

By NexGama Studio · Updated October 22, 2026 · 1 min read

Try it now: Compress PDF — free, no upload.Open tool

“Maximum file size 1 MB” is one of the most common upload errors. Scanned documents are usually to blame: every page is stored as a high-resolution photo. Here are the methods that work, from quickest to most thorough.

1. Compress the PDF

Open Compress PDF and drop in your file.
Start with Recommended. If it’s still too big, try Strong.
For black-and-white documents such as certificates and letters, tick Convert to greyscale — this often halves the size again.

The tool re-renders each page as an optimised image. Text stays readable, but it is no longer selectable, so keep your original if you need to copy from it.

2. Remove pages you don’t need

A blank back side, an instructions page or a duplicate scan all add weight. Use Split PDF with Extract into one file and list only the pages you want, such as 1-3, 5.

3. Scan smarter next time

Scan at 150–200 DPI, not 600 DPI. Forms rarely need more.
Choose greyscale or black & white mode for text documents.
If you photograph pages with your phone, crop them tightly and convert with Image to PDF using A4 size — the result is usually much smaller than a camera “scan” app’s default.

4. Split one big file into parts

Some portals allow several uploads but limit each file. Split the document into two or three parts with Split PDF and upload them separately, naming them clearly (e.g. degree-part1.pdf).

What size can you realistically reach?

Document	Typical original	After compression
1-page colour scan	1–3 MB	150–400 KB
1-page greyscale scan	0.8–2 MB	80–200 KB
10-page scanned report	10–25 MB	1.5–4 MB
Text PDF exported from Word	100–300 KB	Already small — leave it

When compression won’t help

PDFs created directly from Word, Google Docs or other software are already efficient. If one of these is too big, the cause is usually large embedded photos: compress the images before inserting them and export the PDF again.

Tools used in this guide

Compress PDFShrink scanned or image-heavy PDFs. Split PDFPull out page ranges or split every page. Image to PDFCombine JPG/PNG images into a single PDF.