Question 1

How does PDF compression work?

Accepted Answer

Our PDF compressor reduces file size by resampling images to lower DPI (72-150 DPI depending on compression level) and applying JPEG compression. Text remains unchanged.

Question 2

What compression level should I use?

Accepted Answer

Low (150 DPI) maintains near-original quality. Medium (120 DPI) balances quality and size. High (96 DPI) is good for web. Extreme (72 DPI) maximizes compression.

Question 3

Are my PDFs uploaded to a server?

Accepted Answer

No — all processing runs in your browser using PDF-lib and PDF.js. Your files never leave your device.

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