How to Compress a PDF on iPhone or Android
You do not need to install an app to shrink a PDF on your phone. Any modern mobile browser can do it, and the file stays on your device the whole time.
No app required
Most app-store PDF tools either upload your file to a server or push you toward a paid plan. You can avoid both. KiloPDF works in the mobile browser on iPhone and Android and processes the document on the phone itself, so nothing is uploaded.
That matters on a phone, where the document is often a photo of an ID, a bank statement, or a signed form that you would rather not hand to a random service.
On iPhone (Safari)
Open the tool in Safari. Tap the upload area and choose your PDF from Files, iCloud Drive, or wherever it is saved. If you only have a paper document, use the Notes app or the Files app to scan it to PDF first, then pick that file.
Set your target size, tap to compress, and save the smaller PDF back to Files. From there you can attach it to an email or share it through any app.
On Android (Chrome)
Open the tool in Chrome and tap the upload area to pick your PDF from Downloads, Drive, or your file manager. To turn a paper document into a PDF, scan it with Google Drive or your camera app first.
Choose the target size, compress, and the smaller file downloads to your phone. Then share it through Gmail, WhatsApp, or whichever app you need.
Ready to compress your PDF?
Compress PDF to 1 MBFrequently asked questions
Do I need to install an app to compress a PDF on my phone?
No. KiloPDF runs in the mobile browser on both iPhone and Android, and the file is processed on the device, so there is nothing to install.
Is it safe to compress sensitive documents on my phone?
Yes. The file never leaves your phone because the compression happens in the browser, not on a server.