Compress PDF
Smart PDF compression with Lossless, Balanced, Strong & Extreme modes
Compress PDF Documents — Reduce File Size Free Online
DocTools.CC is a free online PDF compressor that reduces file size without making text pixelated or blurry. Whether you need to shrink a scanned document for email, get a file under 500KB for a web form, or simply save storage space, our Smart Router picks the right algorithm for your document type.
Four Compression Modes
- Lossless — Zero quality loss. Best for contracts, signed documents, and legal files. Typical savings: 5–20%.
- Balanced — The default mode and best trade-off. Good quality with meaningful size reduction. Typical savings: 35–60%.
- Strong — Aggressive compression ideal for email attachments and sharing. Typical savings: 55–75%.
- Extreme — Uses JBIG2 and MRC technology (the same as paid tools like Orpalis PDF Reducer) for scanned documents. Can reduce scans by 75–90% while keeping text perfectly readable.
Why Our Compressor Is Different
Most free PDF compressors apply a single compression preset to every page — re-encoding everything as low-quality JPEG, which makes text blurry. Our Smart Router analyzes your PDF first: text-only pages get lossless optimization, mixed pages get balanced treatment, and scanned pages get JBIG2/MRC encoding that keeps text sharp even at extreme compression levels.
Common Use Cases
- Compress PDF documents for email attachments (under 25MB limit)
- Reduce scanned PDFs for web uploads or form submissions
- Shrink large PDF files to under 500KB for size-restricted platforms
- Optimize PDF documents for web hosting and fast downloads
How to Use
- Upload your PDF file (up to 100MB)
- Choose a compression level — start with Balanced
- Click Compress and wait for processing
- Preview the result size and download your compressed PDF
Key Features
- 100% free with no daily limits and no watermarks
- No registration or account needed
- Smart Router auto-selects the best algorithm per page
- Digital signatures preserved automatically (Lossless fallback)
- Files automatically deleted after 30 minutes
- Already-optimized detection — no wasted downloads
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.
Most email providers limit attachments to 25MB. Choose Strong compression for general documents — it typically reduces file size by 55–75% while keeping content clear. For scanned documents, Extreme mode can shrink files by up to 90%, making even large scans easy to attach.
Yes, many users need small files for web uploads or form submissions. Start with Strong mode — if the result is still too large, try Extreme (especially for scanned documents). For text-heavy documents, Balanced may already bring you under 500KB. The tool shows the output size before you download.
Yes — completely free with no daily limits, no watermarks, and no registration. Unlike paid tools that charge per document, DocTools.CC lets you compress as many PDF files as you need at zero cost.