PDF Password Protect
Re-saves your PDF using pdf-lib. NOTE: real AES-256 password encryption requires native libraries not available in browser JS. For true password protection, use qpdf (free CLI), Adobe Acrobat, or macOS Preview. We will not pretend to encrypt when we cannot.
• qpdf (free CLI):
qpdf --encrypt USER OWNER 256 -- input.pdf out.pdf• Adobe Acrobat: File → Protect Using Password
• Preview (macOS): File → Export → Encrypt
What powers the PDF Password Protect
Browser-side PDF re-save
Clear documentation of real encryption options (qpdf, Acrobat, Preview)
Why the PDF Password Protect is different
Browser-native
The PDF Password Protect runs entirely in your browser. Input is processed locally — never uploaded, never logged, never cached anywhere outside your device.
No artificial limits
No daily quotas, no character ceilings, no "upgrade for more" walls. Every feature is the complete feature — the same on the first use as the thousandth.
Production-grade quality
Built to the same engineering bar as paid SaaS tools — accurate algorithms, audited logic, responsive design and accessibility-tested interactions.
Common use contexts
- Learning what tool to use for real encryption
Private and secure
Zero upload
All processing happens in your browser. Input is never transmitted, logged or cached.
Works offline
Once the page loads, the tool runs without an internet connection. No network calls happen during use.
No tracking
No accounts, no cookies for tool state. Only aggregate analytics count visits at the page level.