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Compress PDF

Use this free Compress PDF online tool to reduce your PDF file size while maintaining excellent quality. It is built for students, teams, and professionals who need a clean result quickly. Upload, process, and download in a few clicks. Up to 50 MB per file.

Built & maintained by the OptaPDF Team Editorial standards Free · No sign-up · Files auto-deleted in 30 min
Secure TLS/SSL encryption 100% free, no signup Fast browser-based processing
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Drag & drop your files here

or click to browse from your device

Supported formats: .pdf (Max size: 50MB)

🔒 Secure temporary processing. Files are auto-deleted after 30 minutes.

Uploading file contents...

✓

Your File is Ready!

The processing step completed successfully. You can download your finalized file below.

📥 Download Processed File
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How to Use Compress PDF

Complete your task in four clear steps.

1

Step 1

Upload your large PDF file.

2

Step 2

Select your compression level: 'Low', 'Recommended', or 'Extreme'.

3

Step 3

Click 'Compress PDF' to process.

4

Step 4

View original vs compressed sizes, and download your smaller PDF.

Why Choose OptaPDF for Compress PDF?

  • ✅ Choose Low, Recommended, Extreme, or Custom compression based on your size target.
  • ✅ Shows original size, compressed size, and the exact percentage saved after processing.
  • ✅ Best for image-heavy scans, presentations, reports, and documents that are too large to upload.
  • ✅ Files are processed over HTTPS and automatically deleted within 30 minutes.

Security Guarantee

Your upload is protected with TLS/SSL encryption. Files are automatically and permanently deleted from our servers after 30 minutes. We do not read, share, or store your content. OptaPDF works on iOS, Android, Chrome, Safari, Edge, and desktop browsers without an app installation.

Common Uses for Compress PDF

  • Reduce a PDF below an email attachment limit.
  • Shrink scans before uploading to job, visa, school, tax, or court portals.
  • Compress a report with large images before sharing with a client.
  • Make a PDF easier to download on mobile or slower connections.

Best Results Checklist

  • Use Recommended for most documents because it balances size and readability.
  • Use Extreme only when a portal has a strict size limit.
  • Use Low when the file contains charts, diagrams, or text that must stay crisp.
  • If the PDF is mostly text, compression may be small because there is little image data to reduce.

Troubleshooting Compress PDF

Quick fixes for common file and output issues.

Text-only PDFs are already compact. Large savings usually come from scanned images and photos.
Retry with Recommended or Low compression instead of Extreme.
Check the portal's exact size limit and try a stronger compression profile or remove unnecessary pages first.

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Frequently Asked Questions About Compress PDF

Get answers to common queries regarding security, speeds, and bounds of this tool.

Choose the 'Extreme' compression level, which applies the most aggressive image downsampling for the smallest possible file. If you need to hit a specific target, use 'Custom' and drag the slider to set your own reduction percentage.
We offer: 'Extreme' (maximum compression, smaller file size, slight quality loss), 'Recommended' (perfect balance of quality and size), and 'Low' (high quality, less compression).
Yes, OptaPDF offers 100% free compression without any pricing plans, premium tiers, or download watermarks.
No, our optimization engine focuses on down-scaling high-res images and cleaning up redundant metadata, leaving text sharp and readable.
Depending on the images inside your PDF, file sizes can often be compressed by 30% to 90%.
Yes, we prioritize security. All uploads are encrypted in transit and automatically deleted within 30 minutes of completion.
The output file will have '_compressed.pdf' appended to its base name (e.g., x_compressed.pdf).
You must decrypt the PDF with our Unlock PDF tool before compressing it.
Yes! The results section clearly shows the original size, the revised size, and the percentage of saved space.
Yes, our responsive tool works on all mobile and tablet browsers.
Try running it with the 'Extreme Compression' setting to get the smallest possible file size.