PDF Compressor — Compress PDF Files Online Free

Free, private, serverless PDF compressor. Reduce PDF file size in your browser using pdf-lib — no upload, 100% client-side.

🔒 100% Private
Completely Free
🌐 Runs in Browser
📦 Export Ready

PDF Compressor — Compress PDF Files Online Free

Tool Workspace

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  1. Upload: Drag and drop or click to upload a PDF file.
  2. Compress: Click 'Compress PDF' — the file is re-structured using object streams and metadata is stripped.
  3. Compare: See original vs compressed file size with percentage reduction.
  4. Download: Save the compressed PDF.

PDF Compressor — Reduce PDF File Size in Your Browser

Our PDF Compressor uses pdf-lib to restructure and optimize PDF files entirely in your browser. It reduces file size through lossless techniques — no quality loss, no uploads.

How Compression Works

The compressor applies several optimization techniques:

  • Object streams: Consolidates PDF objects into compressed streams
  • Metadata removal: Strips title, author, subject, keywords, producer, and creator metadata
  • Structure optimization: Rebuilds the PDF cross-reference table for optimal size

What Gets Removed

  • Document metadata (title, author, subject, keywords)
  • Producer and creator information
  • Redundant object definitions

What Stays Intact

  • All text content
  • Images and graphics
  • Fonts and formatting
  • Bookmarks and links
  • Form fields

Common Use Cases

  • Email attachments: Reduce PDF size to fit email limits
  • Web uploads: Optimize PDFs for website or portal uploads
  • Storage: Save disk space with smaller PDF files
  • Sharing: Faster downloads for recipients

Privacy

All processing happens locally in your browser. No PDF data is transmitted to any server.

Frequently Asked Questions

Is my data safe?

Yes. All compression happens in your browser using pdf-lib. No PDF is uploaded to any server.

How much compression can I expect?

Results vary. PDFs with large metadata, duplicate objects, or non-optimized structure can see 10-50% reduction. Already optimized PDFs may not shrink much.

Does compression affect quality?

No. This tool uses lossless compression techniques — restructuring object streams and removing metadata. Text, images, and formatting remain unchanged.