There is no built-in PDF compressor on iPhone. Most apps require a subscription. Here's how to compress a PDF on iPhone for free using only Safari — no app download needed.
Open Safari on your iPhone and navigate to pdfeditor.onl/compress-pdf. The page loads fully in Safari — no app installation required.
Tap the upload area and choose your PDF from Files, iCloud Drive, or any connected storage. The file is loaded into your browser's memory only.
Tip: If your PDF is in an email attachment, use the Share menu in Mail and choose "Save to Files" first, then open it from the compressor.
Choose Good for most use cases. Tap Compress Now and wait a few seconds. Tap Download Result to save the compressed PDF back to your Files app.
Yes. Any iPhone running iOS 14 or later with Safari supports WebAssembly and can run the compressor without issues.
Yes. After downloading, tap the Share icon in Safari to AirDrop, email, or save the file to any app.
The limit depends on your iPhone's available RAM. Most iPhones handle PDFs up to 100 MB comfortably in Safari.