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HomePDF ToolsCompress PDF

Compress PDF — Reduce File Size Online Free

Reduce PDF file size online while preserving all pages and content quality.

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Convert JPG, PNG, and WebP images into a single PDF document with custom page order.

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PDF to Excel

Extract table-like rows from PDF files and export to .xlsx or .csv spreadsheets.

PDF to JPG

Convert PDF pages into high-quality JPG images with adjustable resolution and quality.

How to Use

  1. 1Upload your PDF file by clicking the drop zone or dragging it in.
  2. 2Click Compress PDF to start the optimization process.
  3. 3Compare the original and compressed file sizes shown on screen.
  4. 4Download the optimized PDF file to your device.

About Compress PDF

The Compress PDF tool rebuilds your document with optimized object streams to reduce file size while preserving every page and its visual content. See the before-and-after size comparison so you know exactly how much space you saved.

PDF compression is essential for meeting email attachment limits (typically 10–25 MB), uploading to portals with file size caps, and speeding up downloads. Even modest reductions can prevent a file from being rejected by size-restricted systems.

Results depend on how the original PDF was created. Documents with embedded high-resolution images, unused fonts, or redundant objects compress significantly. Already-optimized PDFs may show little reduction — that is expected, not a limitation.

All compression runs locally in your browser. Your PDF is never uploaded to any server, making this tool safe for tax returns, legal filings, medical records, and any file you would not want on a third-party service.

Frequently Asked Questions

Will compressing my PDF reduce its quality?

Most documents maintain their visual quality after compression. The tool optimizes internal PDF structures and object streams rather than aggressively down-sampling images.

Does this always make the PDF smaller?

Not always. PDFs that are already optimized or very small may show little to no size reduction. The tool works best on documents with embedded images, unused fonts, or redundant data.

Is my PDF uploaded to a server?

No. All compression happens locally in your browser using JavaScript. Your file never leaves your device, so it is safe for sensitive or confidential documents.

What is the maximum file size I can compress?

There is no hard limit, but very large PDFs (over 100 MB) may be slow to process in the browser. For best results, files under 50 MB process quickly.

Can I compress password-protected PDFs?

If the PDF requires a password to open, you will need to unlock it first. PDFs with only print/edit restrictions (owner password) can usually be processed normally.

Explore Other Categories

Text Tools(11)Converters(15)Generators(11)Calculators(10)Developer Tools(18)Image Tools(15)SEO Tools(8)

Related Tools

JPG to PDF

Convert JPG, PNG, and WebP images into a single PDF document with custom page order.

Merge PDF

Combine multiple PDF files into a single PDF in your preferred order.

PDF to Excel

Extract table-like rows from PDF files and export to .xlsx or .csv spreadsheets.

PDF to JPG

Convert PDF pages into high-quality JPG images with adjustable resolution and quality.