How to make a PDF smaller without making it hard to read
By PDFEditor.ae · Published
Start with the limit you actually have
Before changing anything, find the exact limit: the size the upload form or email service accepts, and whether it counts each file or the total. Note how far over you are. A file that is 10% too big needs a different fix from one that is five times too big.
Our tools accept files up to 100 MB each, but the place you are sending to usually has a much lower limit.
Step 1: Try lossless compression
Compress PDF rewrites the internal structure of the file more compactly. It does not touch the text or re-encode images, so nothing becomes harder to read. The tool shows the size before and after.
In our own test, a 24-page text report printed to PDF from a web browser went from 260 KB to 105 KB, a 59% reduction. A PDF of four photos did not shrink at all. Text-heavy files usually gain the most.
- Open Compress PDF and upload the file.
- Click Compress.
- Check the before and after sizes.
- Download the result and open it to confirm it looks the same.
Step 2: If photos make the file big, shrink the photos
Photos and scans are already compressed images, so lossless optimisation cannot do much with them. The reliable fix is to make the images smaller before they go into the PDF: resize or crop the photos on your phone or computer, then convert them again with JPG to PDF.
Aim for photos that are readable on screen rather than full camera resolution. A document photo rarely needs to be wider than about 2,000 pixels.
Step 3: Remove pages nobody needs
Blank backs of scanned pages, cover sheets and duplicate pages all add size. Removing them is the only reduction that never costs readability.
Check readability before you send
- Open the smaller file and zoom to 100%: small print, stamps and signatures should still be clear.
- Check the page count matches what you expect.
- If the form allows several files, splitting a large PDF can be simpler than shrinking it.