MammothPDF
Tools

Compress PDF

Shrink a PDF by re-compressing its images and tidying its structure - on your own device, with the quality trade-off you choose.

Drop PDF files here

Drag them straight from your desktop

or
  • PDF files only
  • Up to 25 MB each

Frequently asked questions

How does PDF compression work here?

Images are resampled to a target resolution and re-encoded, duplicate embedded fonts are folded into one, page content is trimmed and the file structure is rewritten. Text is never rasterised - it stays sharp and selectable.

Which level should I choose?

Light keeps photo quality for print, Balanced suits screens and office printing, Strong is for e-mail and archives. If a file cannot be made smaller it is returned as is, not made worse.

Is the file uploaded?

Nothing is uploaded: the file is opened and processed inside your browser and never leaves your device. Close the tab and it is gone. Even a 50 MB file is compressed on your own machine.

Missing something, or did the result surprise you?