PDF Compressor
Reduce PDF file size while preserving quality. No upload, 100% private – all processing in your browser.
What is PDF compression and why use it?
PDF compression reduces the file size of a PDF document by optimizing or removing redundant data. This makes files smaller, faster to upload/download, and easier to email or share online – all while preserving the essential content.
Common use cases
- Email attachments: Many email servers have file size limits (often 10–25 MB). Compression ensures your PDF fits.
- Website uploads: Faster loading times for PDFs on your site improves user experience and SEO.
- Archiving: Save storage space when storing large collections of documents.
- Sharing: Smaller files are quicker to upload and download from cloud services.
How does PDF compression work?
Compression works by:
- Optimizing images: Reducing resolution or applying more efficient compression.
- Removing redundant data: Eliminating duplicate fonts, objects, or metadata.
- Streamlining the file structure: Reorganizing how data is stored.
Our tool uses lossless compression by default, but you can adjust the quality slider to find the perfect balance between file size and visual fidelity.
Click to upload or drag and drop a PDF file
Only one PDF file at a time
Your compressed PDF is ready!
Why use Pencilfree PDF Compressor?
100% Private
Your files never leave your device. No upload, no server, no storage.
Unlimited & Free
No limits, no sign‑up, no payments. Compress as many PDFs as you want.
Blazing Fast
Client‑side processing means instant results – no waiting for uploads.
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Frequently Asked Questions
How much can I compress a PDF?
Compression ratio depends on the content. Text compresses very well; images may compress less. Typically you can reduce file size by 30–80%.
Does compression affect quality?
Lower quality settings will reduce image quality. Use the slider to balance size and quality. "Lossless" preserves original quality but may not reduce size much.
Are my files uploaded?
No. All processing happens in your browser. Your files never leave your device.
Is there a limit on file size?
There's no hard limit, but very large files may take longer to process. The tool is optimized for typical PDFs (up to 50 MB).