Compress PDF - Reduce PDF File Size Online
Compress PDF files online for free. Reduce PDF file size while maintaining quality. 100% private - files stay on your device.
Compress PDF
Reduce your PDF file size by re-rendering pages at compressed quality. 100% private â all processing happens in your browser.
Drop a PDF here or click to upload
Works best on scanned documents and image-heavy PDFs
file.pdf
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Compression Complete!
Free Online PDF Compressor â Reduce PDF File Size Instantly
Reduce PDF file size without installing software. Our free PDF compressor works entirely in your browser â your files never leave your device. Choose from three compression levels (Maximum, Balanced, High Quality) and adjust page resolution to find the right balance between file size and visual clarity.
How It Works
The compressor renders each PDF page using PDF.js (the same engine used in Firefox's PDF viewer), re-encodes the page as a JPEG image at your chosen quality level, then repacks all pages into a new PDF using pdf-lib. This approach works best for scanned documents, photo albums, and image-heavy PDFs.
Compression Levels
- Maximum (50% quality): Smallest possible file. Good for email attachments where file size is critical and perfect quality isn't required.
- Balanced (72% quality): Best balance of size reduction and visual quality. Recommended for most use cases.
- High Quality (90% quality): Near-lossless compression with modest file size reduction. Good when quality preservation is important.
Best Use Cases
- Scanned documents: Compress scanned contracts, receipts, or forms before emailing
- Photo portfolios: Reduce size of PDF portfolios with many high-resolution photos
- Email attachments: Meet email attachment size limits (typically 10-25MB)
- Web uploads: Reduce size before uploading to portals with file size restrictions