PDF Compressor

By the FastFreeTools Editorial Team · Last reviewed: May 2026 · See our Editorial Policy for methodology, sourcing, and disclaimers.

Reduce PDF file size by optimizing internal structures. Image-heavy PDFs can shrink by 30-70%. Perfect for email attachments.

About this tool

Large PDF files can be problematic for email attachments, web uploads, and storage. Our PDF Compressor reduces file size by optimizing internal data structures, removing redundant information, and recompressing embedded content. The compression algorithm works directly in your browser, so your documents remain private throughout the process. Image-heavy PDFs typically see the most dramatic reductions (30-70% smaller), while text-focused documents may see more modest improvements since text data is already relatively compact. This tool is essential for meeting email attachment limits (typically 10-25MB), improving download speeds for web-hosted documents, and reducing storage costs for large document archives.

How to use PDF Compressor

  1. Upload your PDF file that needs to be compressed.
  2. Wait for the compression algorithm to process your document.
  3. Review the compression results showing original and new file sizes.
  4. Download the compressed PDF with reduced file size.

Tips & best practices

  • Image-heavy PDFs typically see the most compression, sometimes 50-80% reduction.
  • Text-based PDFs may not compress significantly as text is already efficient.
  • Quality is optimized to maintain readability while reducing file size.
  • If the compressed file is still too large, consider splitting the PDF into smaller parts.

Common use cases

  • Reducing PDF size to meet email attachment limits (typically 10-25MB).
  • Compressing large reports and presentations for faster web downloads.
  • Optimizing PDF documents for mobile viewing with limited bandwidth.
  • Preparing documents for upload to systems with file size restrictions.

Privacy

This tool runs entirely in your browser. We do not upload, store, log, or process your input on any server. Open your browser's DevTools Network tab to verify — there is no outbound request with your data. See our Privacy Policy for details.

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