Free Compress PDF Online
Compress PDF files to reduce file size while maintaining quality. Choose between different compression levels. Fast and free.
Compress PDF — launching Summer 2026
The in-browser compress pdf tool is in private beta. Join the waitlist to be notified when it goes live and to get early access.
Join the WaitlistKey Compress PDF Features
How to Compress PDF Online
Follow these simple steps to compress pdf your files in seconds.
Upload your PDF
Drag and drop or select the PDF file you want to compress.
Choose compression level
Select your preferred compression level: low (best quality), medium (balanced), or high (smallest size).
Compress and download
Click 'Compress PDF' and download your optimized file with the reduced size.
About the Compress PDF Tool
Large PDF files can be a hassle to share and store. SublimePDF's Compress PDF tool intelligently reduces file size while preserving the quality that matters. Our smart compression engine analyzes your document and optimizes images, fonts, and metadata to achieve the best possible size reduction. Choose from three compression levels to balance quality and file size for your specific needs.
Why Use Compress PDF Online?
SublimePDF's compression engine analyzes each PDF object independently — downsampling images, subsetting fonts, and removing duplicate resources while leaving text vectors untouched. The result is dramatically smaller files with text that stays razor-sharp at any zoom level.
- Completely free — no registration, no watermarks, no hidden fees.
- Private by design — files stay on your device; nothing is uploaded.
- Instant results — browser-based processing means no waiting for server queues.
- Works everywhere — Chrome, Firefox, Safari, and Edge on desktop, tablet, or mobile.
Privacy & Security
Your privacy matters. When you use SublimePDF's Compress PDF tool, all processing happens directly in your web browser using WebAssembly technology. Your files are never uploaded to our servers, never stored, and never seen by anyone but you.
About the PDF Format
PDF (Portable Document Format) was developed by Adobe and standardized as ISO 32000. It preserves document formatting across all devices and platforms, making it the universal standard for sharing and archiving documents.