How it works
Each page is redrawn as an optimized image at the resolution you choose, then packed into a new PDF. For scans and photo-heavy documents this usually cuts the size dramatically. "Grayscale" removes color for an even smaller file — ideal for forms and contracts.
When to use something else
Because pages become images, text in the result can't be selected or searched. If your PDF is mostly digital text (like an exported report), it's probably already small — the tool will tell you if it couldn't make it any smaller, so you can keep the original.
Frequently asked questions
Which level should I pick?
Balanced works for most documents. Use Strong when you must get under a strict limit, and Light for documents with small print.
Is my document uploaded?
No. Compression happens in your browser using the same PDF engine Firefox uses.
Why can't I select text afterwards?
Pages are converted to images to make them smaller. Keep the original if you need searchable text.