How to make a PDF smaller without losing readability

Why PDFs get big, which size to aim for on government and job portals, and how to compress step by step.

Updated 09 Oct 2026 · by Mustfa Software

Many online forms accept only small files: often 200 KB, 500 KB, 1 MB or 2 MB. A PDF made from phone photos or a scanner can easily be 5–20 MB. This guide explains where the size comes from and how to bring it down while the text stays sharp.

Why is my PDF so big?

• Scanned pages are pictures. A page scanned in colour at 600 dpi can be several megabytes by itself.
• Phone photos are huge. A 12–50 megapixel photo is far more detail than an A4 page needs.
• Embedded fonts and duplicate images add a little more, especially in PDFs made by joining many files.

Pick the right target

Step by step in RakshaPDF Reader

1. Open the PDF and choose Compress PDF.
2. Pick Best quality to remove waste only, or Medium / Small / Smallest.
3. For a portal limit, type the size in Custom size (for example 190 KB, a little under a 200 KB limit).
4. Press Compress, then open the new file and zoom in on small print before you upload it.

Tips that make the biggest difference

• Scan at 150–200 dpi for normal documents; 300 dpi only for tiny print.
• Use Greyscale or B&W for text pages: colour triples the size and adds nothing to black ink.
• Crop the table or floor out of phone photos before making the PDF.
• Compress once from the original. Compressing an already compressed file again makes text blurry.
• Remove pages the form does not need (blank backs, instructions) with Organize pages.

Always keep the original file. Compression for a portal is a copy, not a replacement.