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Compress PDF

Reduce file size while maintaining quality

Drop your PDF file here

or click to browse - up to 100 MB per file

Compression Level

Add a PDF file first

Add a PDF file first

Practical guides
How to Compress a PDF Under 1MB for EmailHow to Merge PDFs in the Correct Order Every TimeHow to Prepare a PDF for Long-Term Archive (PDF/A)
How to use this tool well

How to use this tool well

Compress PDF

Reduce PDF file size online while preserving readability. Share large PDFs faster by compressing in one step.

Use one clean processing pass, then do a quick QA review before you share the result.

Good fit for

  • Meet email attachment size limits.
  • Optimize PDFs before uploading to portals.
  • Lower storage usage for archived document sets.

Typical workflow

  1. 1. Upload your file to the Compress PDF tool.
  2. 2. Choose processing options to match your output needs.
  3. 3. Process and download the result when ready.

Check before you share

  • Review first, middle, and last pages after processing.
  • Check text, tables, signatures, or stamps at 100% zoom.
  • If something looks off, change one setting and rerun once.

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Combine multiple PDF files into one document online. Reorder input files before merging for a clean final output.

Images to PDF

Convert JPG, PNG, and WebP images to PDF online. Reorder images and build a clean multi-page PDF document.

FAQ

Will compressing a PDF reduce image quality?

Standard compression reduces file size by optimizing internal structure and images. SentryPDF offers a standard preset that balances quality and size reduction. For documents with critical images, preview results before sharing.

What is the maximum file size I can compress?

File size limits depend on your usage tier. Guest users can upload files within the default limit. Larger files may require a signed-in account or Pro subscription.

Why is my compressed PDF still large?

PDFs containing high-resolution images or embedded fonts are harder to compress significantly. If your PDF is already optimized or contains scanned images at high DPI, the reduction may be minimal.

Can I compress a password-protected PDF?

No. Password-protected PDFs must be unlocked first. Use the Unlock PDF tool to remove the password, then compress, and protect again if needed.

Does SentryPDF keep my files after compressing?

No. Files are stored temporarily in an isolated processing environment and automatically deleted within 30 minutes. Download your result promptly.

Explore more PDF tasks

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Compression Level

Add a PDF file first

Add a PDF file first

Related guides for this tool

Open tool: Compress PDF

Step-by-step guides

How to Compress a PDF Under 1MB for EmailHow to Merge PDFs in the Correct Order Every TimeHow to Prepare a PDF for Long-Term Archive (PDF/A)All guides

Workflow guides

Compress PDF for Email Attachment LimitsCompress PDF for LMS and Classroom Upload LimitsCompress PDF for WhatsApp and Mobile Chat SharingAll workflow guides