How to compress a PDF
- Drop a PDF into the box above, or choose one.
- Pick Smallest, Balanced or High quality.
- Select Compress PDF, check the new size, then download the smaller file.
What gets smaller, and what doesn't
The tool looks for the photos and scanned pages inside the PDF. Each one is resized to the resolution you choose, based on how large it appears on the page, and saved as a JPEG. A new image is only used when it's clearly smaller than the old one, and if the whole file doesn't shrink you get your original back, unchanged.
Text, fonts, vector drawings, links and bookmarks aren't touched, so text stays sharp and selectable. That also means a PDF made mostly of text won't get much smaller: there's little in it to compress.
Compression levels
| Level | Image resolution | JPEG quality | Good for |
|---|---|---|---|
| Smallest | Up to 110 dpi | 60 | Strict upload limits, reading on screen |
| Balanced | Up to 150 dpi | 72 | Email, sharing and most forms |
| High quality | Up to 220 dpi | 82 | Documents you'll print |
Images that are already at or below the chosen resolution keep their size and are only re-encoded, and kept only if that saves space.
Common uses
- An email attachment that's too big. Many email services cap attachments at 20 to 25 MB. Compressing a scanned contract or photo-filled report usually brings it well under the limit.
- Upload limits on forms and portals. Job, visa and exam portals often accept PDFs of only 1 to 5 MB. Try Balanced first, and Smallest if the file still doesn't fit.
- Phone scans of documents. Scanning apps save every page as a large photo. Compressing keeps the pages readable while cutting the file to a fraction of its size.
- Presentations exported to PDF. Slides full of photos turn into heavy PDFs. Shrinking the images makes the handout quick to share and download.