Compress & Reduce PDF Size
Adjust compression levels tailored to your needs.
or drop files here
Supports multiple files • 100% local process in your device
100% local process in your device • No uploads to any remote server
How does auto-detection work?
• We check the average page size. Files >200KB/page usually contain scans or images, while smaller files are mostly text/vectors.
• Text-heavy → Text Mode (strips metadata, keeps text sharp & selectable).
• Image-heavy → Image Mode (rasterizes & compresses for maximum size reduction).
• You can always override the recommendation manually.
How to Compress PDF Files Online
Reduce your PDF file size for email, web upload, or storage without losing quality. Our smart engine automatically detects the best compression strategy for your document.
Upload Your PDF
Click Select PDF files or drag and drop your document. You can upload multiple files at once to compress them in batch.
Choose Compression Mode
Our tool analyzes your file and recommends the best mode, but you have full control:
- Text Mode (Recommended for documents): Optimizes structure and removes hidden data without converting text to images. Keeps text searchable and links clickable. Typical reduction: 3-30%.
- Image Mode (Recommended for scans/photos): Compresses images inside the PDF by adjusting quality and DPI. Ideal for scanned documents or image-heavy files. Typical reduction: 20-90%.
For Image Mode, you can further adjust the compression level from Low (high quality) to Strong (smallest size).
Compress & Download
Click Optimize PDF. Once processed, you'll see the exact size reduction percentage. Download individual files or get them all in a convenient ZIP archive.
Why Choose CedarPDF for Compression?
Smart Dual-Engine Compression
Unlike basic tools that use a one-size-fits-all approach, we offer two specialized modes. Text Mode preserves vector quality for documents, while Image Mode aggressively optimizes scans and photos for maximum size reduction.
100% Private & Secure
Compressing documents often involves sensitive data like contracts or financial reports. CedarPDF processes everything locally in your browser. Your files never leave your device, ensuring complete confidentiality.
Full Quality Control
Don't guess the result. Our interactive sliders let you preview the trade-off between file size and quality. Choose "Low Compression" for archival quality or "Strong Compression" for email attachments.
Completely Free & Unlimited
No hidden fees, no watermarks, and no daily limits. Compress as many PDFs as you need, regardless of file size (up to 100MB per file), completely for free.
Frequently Asked Questions
What is the difference between Text Mode and Image Mode?
Image Mode is designed for scanned documents or PDFs with many photos. It rasterizes pages into high-quality images and compresses them, achieving much higher size reduction but making text non-searchable.