Compress PDF
Guide & FAQCompression level
Guide: Compress PDF
Choose a PDF, pick a compression level and press Compress. You see the size before and after. It is free and unlimited, with no sign-up, no watermark and no upload.
How it works
This tool shrinks the pictures inside a PDF. It re-encodes each embedded image as a JPEG at your chosen quality, and scales down images that are drawn at a higher resolution than your DPI limit. Fonts, text and vector graphics are not touched.
Levels
- Light: quality 85, up to 220 DPI. Pictures stay sharp.
- Recommended: quality 70, up to 150 DPI. Good for screens and email.
- Strong: quality 50, up to 100 DPI. Smallest file, softer pictures.
- Custom: move the sliders yourself.
An honest result
A scan or a photo-heavy PDF can shrink a lot. A PDF that is mostly text may not shrink at all. When there is no real gain, the tool tells you and does not hand you a file that is no smaller. If you want a smaller result, try a lower quality or DPI.
Good to know
- Your files are processed inside your browser tab and are not uploaded.
- Password-protected PDFs must be unlocked first.
- Only JPEG pictures and plain RGB or grey pictures are re-encoded; other image types are left alone.
FAQ
How does it make the PDF smaller?
It finds the pictures inside the PDF and re-encodes them as JPEG at the quality you choose. Pictures drawn much larger than the DPI limit are also scaled down. Text and vector drawings are left as they are.
Why did my PDF not get smaller?
Many PDFs are mostly text and vector graphics, or their images are already compressed. In that case the tool says so and keeps your original, instead of giving you a file that is no better.
Will the quality drop?
Pictures lose some detail at lower quality settings. Light keeps them sharp, Strong makes them visibly softer. Text stays crisp at every level.
Is there a size limit or daily cap?
No. It is free and unlimited. Very large files depend on your device memory.
Is my PDF uploaded?
No. The pictures are re-encoded by your browser in this tab.
Open-source licences
- pdf-lib: MIT
- PDF.js (legacy build 3.11.174): Apache-2.0