Compress PDF

Reduce PDF file size to save storage space

※ Notice

  • All processing is done in your browser. Files are not uploaded to any server.
  • Reduces file size through PDF structure optimization.
  • PDFs with many images may have higher compression rates.
  • Text and image quality is preserved after compression.

Email Attachment

Reduce file size for email limits

Cloud Storage

Save storage space

Web Upload

Faster upload speeds

Mobile Transfer

Reduce data usage

Frequently Asked Questions

How does PDF compression work?

PDF compression works by removing duplicate data inside the file and optimizing object streams. It reduces file size by cleaning up unnecessary metadata and duplicate font information, and all processing is done within your browser.

Does compression degrade image or text quality?

This tool uses structural optimization compression, so text quality is not affected at all. Images retain their original data, so quality is preserved to a level indistinguishable to the naked eye.

Is there a maximum file size limit for compression?

Since processing is done in the browser without uploading to a server, there is no server-side size limit. However, very large files (100MB+) may process more slowly depending on browser memory.

Can I still search and copy text after compression?

Yes. The structural optimization method preserves the PDF's text layer intact, so text search, copy, and hyperlink functionality all work normally after compression.

Why You Need PDF Compression

PDF compression is an essential solution when email attachments exceed size limits (typically 10–25 MB) or when web upload speeds are slow. Compressed PDFs save cloud storage space and significantly reduce data usage on mobile devices.

Differences Between Compression Levels

Structure optimization compression works by removing unnecessary objects and duplicate data inside the file, making it effective for text-heavy documents. PDFs with many images can achieve higher compression rates through image recompression, and you can generally expect a 10–40% reduction in file size compared to the original.

Additional Tips for Reducing PDF Size

Setting the image resolution appropriately for its intended use when creating a PDF can significantly reduce file size. For on-screen documents, 72–96 DPI is sufficient; for print, 150–300 DPI is enough. Also, removing unnecessary pages before compressing makes it even more effective at reducing file size.

This calculator is provided for informational purposes only.

Results are estimates and may differ from actual amounts.

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