How to compress a PDF online without losing quality

Reduce PDF file size for email and uploads while keeping it readable — free, private, and in your browser.

3 min read · Updated June 9, 2026

Try it now: Compress PDF

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Why PDFs get so large

Most oversized PDFs are heavy because of high-resolution images and embedded fonts. Email attachment limits (often 25 MB) and upload forms that cap at 5 or 10 MB make a bloated PDF a real problem. Compressing it solves this in seconds.

How to compress a PDF

1. Open the Compress PDF tool and add your file.

2. Let it optimise images and structure to shrink the size.

3. Download the smaller file — readable, shareable, and still selectable text.

Your file stays private

Compression runs in your browser. The PDF is never uploaded to a server, so even sensitive documents stay completely on your device.