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Compress PDF

Reduce stored PDF data without lowering image quality.

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How to compress a PDF

  1. Choose an unlocked PDF.
  2. Select Compress PDF to optimise its stored data.
  3. Compare the original and new sizes, then download a copy.

Before you save

  • Lossless compression does not resize images or flatten pages; it cannot guarantee a smaller file.
  • Signed, encrypted and repaired PDFs are refused. Check the result before replacing a working copy.

Useful details

Does compression reduce image quality?

This tool uses lossless compression. It optimises stored data without lowering image resolution.

Why did my PDF stay the same size?

Many PDFs are already compressed. The tool keeps a copy when further lossless reduction is not useful.