Free Compress PDF
Compress PDF makes PDF files smaller by re-encoding the pictures inside them, while text, fonts and vector graphics stay untouched. Choose Screen (72 DPI), Ebook (150 DPI), Print (300 DPI) or Custom, optionally convert images to grayscale or remove metadata, and download several files together as a ZIP. If a file can't get smaller, the original is kept.
- Levels:
- Screen 72, Ebook 150, Print 300 DPI
- Untouched:
- Text, fonts and vector graphics
- Engine:
- QPDF in WebAssembly
- Price:
- Free
- Runs:
- Locally, in your browser
- Uploads:
- None: files never leave your device
- Account:
- Not needed
Quick answers
Will the text get blurry?
No. Only the pictures inside the PDF are recompressed. Text, fonts and vector drawings are kept as they are, so they stay sharp, searchable and selectable.
Which level should I choose?
Ebook (150 DPI) is right for reading on screen and sharing by email. Screen (72 DPI) makes the smallest files but photos look soft when zoomed in. Print (300 DPI) keeps photos sharp on paper while still trimming oversized images.
Processed on your device: your files are never uploaded. How it works
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What this page has requested since you opened the site in this tab. An upload is any request that sends data: POST, PUT, PATCH or a request with a body.
No uploads: nothing has been sent from this page.
No network requests yet.
To see every request, open your browser's developer tools (Network tab).
How to use the Compress PDF
- Pick a compression level: Screen for the smallest files, Ebook for a good balance, Print for high quality, or Custom.
- Drop one or more PDFs: they are compressed one after the other, right in your browser.
- Check the savings and download each file, or all of them as a ZIP.
Read the full guide: How to compress a PDF without losing quality
Credits & open source
Our own code plus open-source libraries. Thank you to the people who make these projects.
- pdf-libCreate and modify PDF documents (merge, split, rotate, stamp, sign). © Andrew Dillon · MIT
- qpdf-wasm (QPDF)QPDF, the PDF transformation tool, compiled to WebAssembly (QPDF itself is Apache-2.0). © neslinesli93 (WebAssembly build); QPDF by Jay Berkenbilt · ISC
- fflateFast ZIP compression for batch downloads. © Arjun Barrett · MIT
Web platform APIs used: File API, Canvas 2D, createImageBitmap, Web Workers, URL API.
Full license texts: third-party notices · all credits
Frequently asked questions
Why didn't my PDF get smaller?
Files made mostly of text, or whose images are already compressed at a low resolution, have little left to remove. In that case the tool keeps your original file instead of making it bigger.
Is my PDF uploaded?
No. The images are re-encoded by your browser and the file is optimized by QPDF compiled to WebAssembly, all on your device.
Can I compress a password-protected PDF?
Not directly. Remove the protection first with the Unlock PDF tool (you need to know the password), then compress the unlocked file.