How to Compress PDF Without Losing Quality

Large PDF files are difficult to share via email and slow to upload. Compression reduces file size while keeping documents readable and professional.

Compression Levels

dokk.ai offers three compression levels to match your needs:

• Low compression — Minimal quality loss, ~20% size reduction. Best for documents with high-resolution images that need to stay sharp.
• Medium compression — Good balance of quality and size, ~50% reduction. Recommended for most documents.
• High compression — Maximum size reduction, ~80% smaller files. Best for archival or web use where file size matters most.

How to Compress a PDF

1. Open the at dokk.ai
2. Upload your PDF file
3. Select your preferred compression level
4. Click Compress and wait for processing
5. Download the compressed file

When to Compress

Compress PDFs before:

• Emailing — Most email providers limit attachments to 25 MB
• Uploading to web forms — Many forms have file size limits
• Archiving — Save storage space for long-term document storage
• Sharing via chat — Messaging apps often compress or reject large files

What Affects PDF Size?

Image Optimization

Images are the biggest factor in PDF file size. During compression, dokk.ai:

• Resamples images to optimal DPI for the chosen quality level
• Converts images to more efficient formats where possible
• Strips unnecessary metadata from embedded images