How to compress a PDF (without losing quality)
Most PDFs are big because of one thing: embedded images. Text and vector paths compress almost for free.
The three levers
- Downsample images to the resolution you actually need (150 DPI for screen, 300 DPI for print).
- Re-encode photos as JPEG at ~75% quality; keep line art as PNG/CCITT.
- Subset fonts — remove glyphs the document doesn't use.
Do it in one click
Compress PDF applies all of this for you — pick Light, Balanced or Strong, drop the file, and compare the before/after pages. Scanned and image-heavy PDFs typically drop 60–90%. Everything runs in your browser; nothing is uploaded.
Printing in black and white? Run PDF to grayscale first for an extra size cut, or split off just the pages you need with Split PDF.