How to Compress PDF on iPhone

The fastest way to compress a PDF on iPhone is to use a browser-based compressor like the one on this site. Open Safari, navigate to the Compress PDF tool, and tap the upload area.

Select 'Photo Library' or 'Files' from the menu that appears. If your PDF is in the Files app (iCloud Drive, Downloads, or a third-party cloud storage app), choose Files. If it's a scan from the Photos app, choose Photo Library.

Once the PDF is uploaded, select your compression level. Recommended is the right choice for most use cases — it reduces file size by 60-80% with no visible quality loss.

Tap Compress. The compression runs entirely on your iPhone — no upload, no waiting on a slow cellular connection. When it's done, tap Download to save the compressed PDF to your Files app.

The whole process takes 10-20 seconds for most PDFs. Because everything happens on-device, it works even on a slow connection or with no connection at all after the page loads.

iPhone's Files app has a built-in PDF workflow that includes basic compression. Open the Files app, find your PDF, long-press it, and choose 'Create PDF' from the menu. This doesn't compress much, but it can help for some file types.

For more aggressive compression, the Files app doesn't have great built-in options. You're better off using a browser-based tool like the one on this site, which offers three compression levels and shows you the resulting file size before you commit.

The Files app is best for organizing and managing PDFs after compression. Once you've compressed a PDF using the browser tool, save it to Files for easy access later.

Adobe Acrobat Reader is a free app from the App Store that includes PDF compression. Open the app, find your PDF, tap the three-dot menu, and choose 'Compress PDF'. The free version offers one compression level; the premium version (paid subscription) offers more control.

Acrobat Reader is a good choice if you work with PDFs frequently and want a dedicated app. For occasional compression, the browser-based tool is faster and doesn't require installing anything.

Note that Adobe Acrobat Reader uploads your PDF to Adobe's servers for compression. If privacy is a concern, use the browser-based tool on this site instead, which processes everything on your iPhone.

Use Wi-Fi when possible. While the browser-based tool processes locally, the initial page load and final download are faster on Wi-Fi.

Save compressed PDFs to iCloud Drive for easy access across all your Apple devices. The Files app makes this easy — just choose iCloud Drive as the save location.

If you compress PDFs frequently, add the tool to your Home Screen. Open Safari, navigate to the Compress PDF page, tap the Share button, and choose 'Add to Home Screen'. This creates an app-like icon that opens the tool directly.

For scanned documents, use the iPhone Notes app's built-in scanner (open a note, tap the camera icon, choose Scan Documents) to create PDFs directly. Then compress them using the browser tool.