Free compress PDF tool online
This free compress PDF tool helps you reduce PDF file size so a big document becomes small enough to email, upload to a form, or store without eating up space. Pick a compression level and the tool shrinks your PDF right in your browser — with no signup, no watermark and nothing to install.
The compression happens locally on your device, so your file is never uploaded to a server. It stays completely private, which makes this a safe way to shrink contracts, statements, scans and other confidential documents.
How to compress a PDF
- Drop your PDF onto the box above, or tap to choose it from your device.
- Choose a compression level — Low, Recommended, or Strong.
- Click Compress PDF and wait a moment while each page is processed.
- Check the before/after size, then download your smaller PDF.
How this compressor works (and what to expect)
To meaningfully make a PDF smaller, this tool re-renders each page and re-compresses it as an optimised image, then rebuilds the document. That is where the size savings come from — especially on scanned documents and image-heavy PDFs, which are usually the largest files people need to shrink.
There is a trade-off to be aware of: because each page is re-rendered, the text in the compressed copy is no longer selectable or searchable. If you need selectable text, keep your original. And because the savings come from images, a text-only PDF is often already small and may not shrink further — the tool will tell you if that is the case.
Why use this compress PDF tool
- Private & secure: your PDF is compressed on your device and never uploaded.
- Real savings on scans: big reductions for scanned and image-heavy PDFs.
- Clear results: see the exact before and after size and percentage saved.
- Simple levels: pick Low, Recommended or Strong — no confusing settings.
- Works everywhere: Windows, Mac, Android and iPhone — no install needed.