Compress PDF — Free Online Tool
Reduce PDF file size for email & upload limits. · No signup · Works on mobile
100% private: your files are processed in your browser. Nothing is uploaded to our servers.
How to use the compress pdf
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Drop your PDF into the tool.
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Pick a level: High quality (light compression), Balanced, or Smallest size.
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Click Compress, check the size reduction, and download the smaller PDF.
What does this tool do?
This free PDF compressor shrinks PDF file sizes — often by 50–90% for scanned documents — so they fit email attachment and portal upload limits. Choose a compression level, see the exact before/after sizes, and download. Compression runs entirely in your browser for full privacy.
How does the compress pdf work?
Scanned and image-heavy PDFs are compressed by re-rendering each page at an optimized resolution and JPEG quality, then rebuilding the PDF — the same approach desktop tools use. Text-based PDFs compress less (they're already efficient); image-heavy files see dramatic savings.
Frequently Asked Questions
Why did my PDF only shrink a little?
The savings depend on what's inside. Scanned/image PDFs typically shrink 60–90%. But text-native PDFs (exported from Word) are already highly compressed — they may only shrink 5–20%. If a text PDF is unexpectedly huge, embedded fonts or hidden attachments are usually the cause.
Will compressed PDFs still be readable and printable?
Yes — the Balanced level targets 110–150 DPI effective resolution, crisp for on-screen reading and acceptable in print. Note that heavy compression converts pages to images, so text may no longer be selectable; keep an original copy if you need selectable text.
Is the PDF compressor really free?
Yes — 100% free with no hidden charges, trial limits, or premium tiers for core features. No account or email needed. The site is supported by non-intrusive display ads, which keeps every tool free for everyone.
Are my files private when using the PDF compressor?
Completely. The PDF compressor processes everything locally in your browser — your files are never uploaded to any server. When you close the tab, everything is gone. This makes it safe for confidential documents, client work, and personal photos.
Does the PDF compressor work on mobile phones?
Yes. It's built mobile-first and works on any modern phone browser — iPhone (Safari) and Android (Chrome) included. You can pick files straight from your camera roll and download results directly to your device.
Do I need to install any software to use the PDF compressor?
No. The PDF compressor runs entirely in your web browser — no downloads, extensions, or signup. Open the page, use the tool, download your result. It works on Windows, macOS, Linux, ChromeOS, iOS, and Android.