How to Compress a PDF on iPhone & iPad

iOS doesn't include a native PDF compressor, but there are a couple of practical approaches that work directly on your iPhone or iPad without needing a computer.

Method 1: Online Tool via Mobile Browser (Easiest)

The simplest method on iPhone and iPad is to use an online PDF compressor directly in Safari or Chrome. No app download required.

1. Open Safari or Chrome on your iPhone or iPad.
2. Go to compress-pdf.cc.
3. Tap the upload area and select "Photo Library" or "Browse" to locate your PDF in Files.
4. Choose your compression level and tap Compress PDF.
5. When the result appears, tap Download Compressed PDF and save it to your Files app.

Method 2: iOS Shortcuts Automation

If you regularly compress PDFs on your iPhone, the Shortcuts app can automate part of the process. However, iOS Shortcuts doesn't have a native "compress PDF" action — you'd need a third-party shortcut or app integration.

The most practical use of Shortcuts is to create a shortcut that opens compress-pdf.cc directly, saving you a few taps each time you need to compress a file.

Method 3: Third-Party Apps

Several apps on the iOS App Store offer PDF compression. Some well-regarded free options include:

• PDF Expert (Readdle): A full-featured PDF editor with compression options. Free to use for basic tasks.
• Scanner Pro: Good for scanned documents; includes export compression options.
• Smallpdf app: The mobile companion to the Smallpdf web service.

Keep in mind that many PDF apps on iOS are freemium — compression may be behind a paywall. An online tool is genuinely free with no limitations.

How to Save the Compressed File on iPhone

1. After compression, tap the download button in your browser.
2. iOS will offer to open the file — instead, tap and hold the download icon in Safari's toolbar, or look for a share sheet option.
3. Tap Save to Files and choose a location (iCloud Drive or On My iPhone).
4. The compressed PDF is now available in the Files app.