How much can a PDF be compressed?

Results vary based on content. PDFs with large embedded images can be reduced by 60-80%. Text-only PDFs have less room for compression — typically 10-30%.

Is my PDF uploaded to a server?

No. PDF compression runs entirely in your browser using the PDF-lib JavaScript library. Your document never leaves your device.

What does each compression level mean?

Screen: lowest resolution, smallest file, for on-screen viewing. eBook: balanced quality, good for most uses. Printer: high quality for printing. Prepress: maximum quality, minimal compression.

Will compression reduce the PDF quality?

Quality reduction depends on the compression level chosen. Screen mode reduces embedded image resolution significantly. Printer and Prepress modes preserve quality well.

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Free PDF Compressor

Compress PDF files free online. Reduce PDF size without losing quality. No upload to server — processed entirely in your browser.

About this tool

Reduce PDF file size online for free. Choose from multiple compression levels — from aggressive screen-optimized compression to light prepress quality. All processing runs in your browser via PDF-lib, so your documents are never uploaded to any server.

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Drop a PDF here or click to browse

PDF files only · Max 50MB

Compression Level

How we calculate this

All calculations run entirely in your browser — no data is sent to any server. Here is exactly how this tool works:

Click "Choose PDF" or drag and drop your PDF file
Select a compression level: Screen (smallest), eBook (balanced), Printer, or Prepress
Click Compress PDF to process the file
Compare original and compressed sizes, then download your smaller PDF

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