PDF Compression Explained: How to Reduce File Size

Why Compress PDFs?

Large PDF files can be problematic for email attachments, website uploads, and storage. Compression helps you:

• Send files via email without size restrictions
• Save storage space on your device or cloud
• Load documents faster on websites
• Share files more quickly

How PDF Compression Works

PDF compression reduces file size by removing redundant data and optimizing how information is stored. This includes:

• Removing metadata: Author names, creation dates, software info
• Optimizing streams: Compressing internal PDF objects
• Image compression: Reducing image quality (if applicable)
• Font subsetting: Including only used font characters

Compression Levels Explained

Low Compression

Best for: Documents where quality is paramount

• Minimal file size reduction (5-15%)
• Preserves most original data
• Fastest processing

Medium Compression

Best for: General use, balanced approach

• Good file size reduction (20-40%)
• Maintains acceptable quality
• Recommended for most users

High Compression

Best for: Email attachments, quick sharing

• Maximum file size reduction (40-60%)
• May slightly reduce quality
• Ideal when size is critical

Best Practices

• Always keep a backup of the original file
• Start with medium compression and adjust as needed
• Test compressed files before sharing
• Consider the end use (print vs. digital)

Try Our Compress Tool

Use our free PDF compression tool to reduce your file sizes instantly with client-side processing for maximum privacy.