How to compress a PDF on an iPhone

There is no built-in way to compress a PDF on an iPhone: the Files app can view, mark up and reorder pages, but it has no size control. The practical answer is a browser tool in Safari, which needs no app and works on an iPad the same way.

Is there a built-in way on an iPhone or iPad?

No. iPhone and iPad has nothing built in for this, and the closest things get in the way:

  • Files can open, annotate and reorder a PDF, but there is no compress or reduce-size command anywhere in iOS or iPadOS.
  • Printing to PDF (Share → Print → pinch the preview) re-renders the file, which usually leaves the size unchanged or makes it larger.

What that means

  • No native compression at all.
  • Mail's own image-size prompt applies to photos you attach, not to a PDF you attach.

Do it in the browser instead

The same Compress PDF tool as the main page, running in Safari on an iPhone or iPad. Nothing is installed and the file is processed on your device.

Processed in your browser. This file never leaves your device.

  1. 01

    Choose the PDF

    Open the tool in Safari, tap Choose file, and pick the document from Files or Photos.

  2. 02

    Pick a mode

    Rebuild keeps the text; Flatten to images is smallest for a scan or a photographed document.

  3. 03

    Download the result

    Tap Compress PDF, then Download. Safari saves the file to Files, where you can share it from Mail or Messages.

Files or the browser tool?

 Built in on iPhone and iPadPDF Spree
CostNo built-in optionFree, no account
Text stays selectableNot applicableYes
File leaves your deviceNot applicableNo — processed in the browser
Works on other devicesNo, this platform onlyYes, any modern browser

Compress PDF on an iPhone or iPad: questions

The same task on other devices

More PDF tasks on an iPhone or iPad

Related tools