Compress PDF
Smart PDF compression with Lossless, Balanced, Strong & Extreme modes
About Compress PDF
Compress PDF is a free online tool that smart pdf compression with lossless, balanced, strong & extreme modes. No registration or software installation required — simply upload your file, adjust settings, and download the result.
How to use Compress PDF
- Upload your PDF file using the upload area above
- Adjust processing options as needed
- Click "Process" and wait for processing
- Download your result file
Key Features
- 100% free with no daily limits
- No registration or account needed
- Files automatically deleted after 30 minutes
- Fast server-side processing
Frequently Asked Questions
Everything you need to know about this tool
Most compressors use a single preset that re-encodes every page image as low-quality JPEG — which blurs text. Our Smart Router analyzes your PDF first and picks the right algorithm: Lossless for text documents, Balanced for mixed content, and JBIG2 + MRC for scans so text stays sharp.
Start with Balanced (the default) — it is the best trade-off. Use Lossless for contracts and signed documents, Strong for email attachments, and Extreme for scanned documents (it uses the same JBIG2/MRC technology as paid tools like Orpalis PDF Reducer).
Extreme uses ocrmypdf with jbig2enc (lossy JBIG2 for text regions) and aggressive image optimization. It takes longer to run but can reduce scanned PDFs by 80–90% while keeping text perfectly readable — much better than plain JPEG recompression.
No. When we detect a digital signature, we automatically use Lossless compression so your signature stays valid. Encrypted PDFs are also handled safely.
If compression would make the file bigger or barely smaller, we return the original file unchanged and tell you "Already optimized" — no wasted download.
Text-only PDFs: 5–20% (Lossless). Mixed documents: 35–60% (Balanced). Aggressive: 55–75% (Strong). Scans: 75–90% (Extreme).
Yes, you can upload PDF files up to 100MB for compression.