Compress PDF Online — Reduce File Size

Rebuild the file to keep the text selectable, or flatten the pages to JPEG at a quality you choose when the file has to get much smaller. Nothing is uploaded.

Upload a file to get started. Processing runs entirely in your browser.

How to use

  1. Drop the PDF in. It is read on your device, not uploaded.
  2. Pick Rebuild to keep the text selectable, or Flatten pages to images and set a JPEG quality and resolution for a much bigger cut.
  3. Click Process, check the before and after sizes, then download.

Frequently asked questions

Which compression method should I pick?

Rebuild the file when the PDF is mostly text and you want it to stay selectable and searchable. Flatten pages to images when the file is a scan or is full of photos and you need it under a hard size cap, such as an email attachment limit.

Why did rebuilding barely shrink my PDF?

Rebuilding repacks the file structure with object streams and drops unreferenced objects. It never touches the images, so a file exported by a modern tool is often already at that size. The tool shows the before and after bytes so you can see it, and suggests flattening when there is nothing left to gain.

What does the JPEG quality setting change?

It only applies to the flatten method. Each page is rendered at the resolution you choose and stored as a JPEG at that quality, so 40 makes a far smaller file with visible artefacts and 90 stays close to the original. It does nothing on the rebuild method, which is why it only appears when flattening is selected.

Does my file get uploaded?

No. The PDF is read, rendered and rewritten by JavaScript in your own browser tab, and the bytes never leave the machine.

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