Compress PDF

Make scanned documents and photo-heavy PDFs small enough to email or upload. Choose a strength and see the size before and after.

Uploaded to servers0 B
Processed locally0 B
Strength

Compression turns each page into an image, so text can no longer be selected or searched. Best for scans and photo-heavy files; text-only PDFs may get larger.

Why your files stay on your device

Nothing is uploaded

Most online PDF sites send your file to their servers. PDFMoss does the work inside your browser, so there is nothing to intercept, store or leak.

No limits on uses

There are no daily caps because there are no servers doing the work. Use any tool as often as you like.

Works on your phone

Every tool works on iPhone and Android: pick photos from your gallery and sign with your finger.

Original quality, works offline

Pages and images keep their quality, and once you install the app the tools work without an internet connection.

How to compress PDF

  1. Drop a PDF on the page or click to choose it.
  2. Choose Strong, Medium or Light compression.
  3. Click Compress and download the smaller PDF.

Frequently asked questions

How much smaller will my PDF get?

Scans and photo-heavy files usually shrink by 40–90%. Text-only PDFs are already compact; if compressing would not help, the tool tells you instead of giving you a bigger file.

Can I still select text after compressing?

No. Compression turns each page into an image, so it suits scans and photos. Keep the original if you need searchable text.

Which level should I pick?

Medium works for most documents. Use Strong for the smallest file when you only need it to be readable, and Light when print quality matters.

Are my files uploaded to a server?

No. PDFMoss processes files inside your browser. The counter at the top of the page shows 0 B uploaded because nothing is sent.

Is PDFMoss free?

Yes. Every tool is free to use with no sign-up and no watermark on your files.

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