How to Reduce PDF File Size (Without Losing Quality)

A PDF that's too big to email is almost always caused by one thing: high-resolution images inside it. Here's why PDFs balloon and how to bring them back down.

Why PDFs get large

• Scanned pages stored as full-resolution images (600 DPI scans are huge).
• Embedded photos at camera resolution.
• Embedded fonts and complex vector graphics (smaller, but they add up).

Ways to shrink a PDF

1. Lower the scan resolution. For documents meant to be read on screen, 150–200 DPI is plenty; 600 DPI quadruples the size for no readable benefit.
2. Compress images before creating the PDF. If you're building a PDF from photos, compress them first — our image compressor can do this in your browser.
3. Remove pages you don't need. Fewer pages = smaller file. Use the PDF tools to delete blank or unnecessary pages.
4. Split a large PDF into smaller parts if you only need to send a section.

Print-to-PDF trick

Opening a PDF and choosing "Print → Save as PDF" sometimes re-encodes it more efficiently, especially for files created by older scanners. It's a quick thing to try.

Keep it private

Many "compress PDF" sites upload your document to their servers. For contracts and confidential files, prefer local tools. Our PDF tools merge, split, delete and rotate entirely in your browser — nothing is uploaded.

FAQ