Can I protect PDF on iPhone without an app?

Yes. Open Safari, select your PDF from Files, enter a password, and save to iCloud Drive. Encryption runs in a Web Worker locally.

How do I protect PDF on Android?

Use Chrome, tap to select your PDF from Drive or downloads, set a passphrase, and download the locked file.

Can I add password to PDF on mobile?

Yes. The protector form is touch-friendly — add password to PDF on mobile the same way as desktop.

How strong is mobile PDF protection?

AES-128/256 or RC4 per PDF standard via pdf-lib — same bank-level encryption as desktop. Use a strong passphrase.

Does lock PDF on phone upload my file?

No. Mobile PDF protection is 100% local — bytes never leave your phone or tablet.

What about protect PDF Windows and Mac?

Edge and Chrome on Windows, Safari on Mac — full-width protector on laptop screens, no dedicated app required.

What if I forget the password on my phone?

PDF passwords cannot be recovered. Keep an unencrypted backup in Files or Drive before you lock PDF on phone.

Protect PDF Cluster

Mobile PDF Protection — Phone & Desktop

Protect PDF on iPhone before a flight, add password to PDF on mobile in Android Chrome, or lock PDF on phone from a tablet — protect PDF Windows and protect PDF Mac users get the same responsive mobile PDF protection with local pdf-lib Web Worker encryption on any screen size.

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How it works

1
Open on phone or desktop browser
No App Store download. Protect PDF on iPhone in Safari, protect PDF on Android in Chrome, or use Edge on Windows and Safari on Mac.
2
Select PDF from Files or Drive
Pick documents from iCloud, Google Drive, or local storage. Add password to PDF on mobile with a touch-friendly form.
3
Lock & save locally
Enter a passphrase and download. Mobile PDF protection processes on-device — files never upload.

Use cases

Travel document security

Protect PDF on iPhone boarding passes and itineraries before sharing on hotel Wi-Fi.

Field invoice locking

Lock PDF on phone when a contractor needs to password-protect a signed invoice before emailing HQ.

Windows without Adobe

Protect PDF Windows 11 workflows in Edge — no Microsoft Store security app purchase.

MacBook quick locks

Protect PDF Mac users encrypt attachments in Safari — full desktop width on MacBook screens.

Problems we solve

OS-specific app stores

Mobile PDF protection in the browser avoids per-platform subscriptions and update hassles.

Desktop-only protector sites

Ours is touch-friendly — add password to PDF on mobile and tablet alike.

Cloud upload on cellular

Local processing means protect PDF on Android or iPhone without sending large files over cellular to a server.

Trust & privacy

Cross-platform one URL

Same tool to protect PDF on iPhone, Android, Windows, and Mac — responsive layout throughout.

Free mobile protection

Standard phone locks stay free without signup.

On-device privacy

Files process locally on mobile — no cloud retention of sensitive documents.

Frequently asked questions

Protect PDF