FreeAPI

Protect PDF with Password Online

AES-256 Encrypt

Military-grade PDF encryption engine for bank statements, payrolls, and legal contracts. Lock documents using AES-256 encryption directly in your browser. Unauthorized viewers cannot read or print without the exact passphrase.

All Tools

Interactive Tool Console

Client-Side Execution • Runs in browser
Password protection and unlocking happen 100% locally in your browser. Passwords are never sent online.
Guest Quota: 2/2

Select or Drag & Drop PDF to Protect

Processed 100% locally with AES-256 standard.

Live API Integration Public Edge API

Call this tool in your codebase or backend services directly via REST API.

curl -X POST "https://findfreeapi.com/api/v1/tools/pdf-protect-unlock" \
  -H "Content-Type: application/json" \
  -d '{"action":"protect","password":"SecretPassword123"}'
POST/api/v1/tools/pdf-protect-unlock
No API Key Required (Public Edge)

Key Standards & Highlights

Apply strong AES password locks to prevent unauthorized opening
Enforces password prompts across Adobe Acrobat, Chrome, Safari, and Edge
Zero cloud transmission: Passwords and documents remain strictly local
High-security document permission restriction

Frequently Asked Questions

How secure is a password-protected PDF?

Protected using standard AES cryptography. Unauthorized viewers cannot read, extract text, or print without the exact passphrase.

Popular Free APIs to Pair With This Tool

Verified free REST APIs that seamlessly complement this utility to accelerate your development workflow.

Explore All 1004+ Free APIs
VirusTotal
security

Dosya ve URL kötü amaçlı yazılım analizi

⚡ 4 istek/dkView API Documentation
HaveIBeenPwned
security

Veri ihlali ve şifre sızıntısı kontrolü

⚡ 10 istek/dkView API Documentation
Auth0
auth

Kurumsal kimlik doğrulama platformu

⚡ DeğişkenView API Documentation
BitWarden
auth

Ücretsiz şifre yöneticisi API'si

⚡ DeğişkenView API Documentation

Explore Other Tools

Secure Password Generator

Generate cryptographically strong random passwords, secure PINs and calculate entropy scores.

Hash & HMAC Generator

Calculate MD5, SHA-1, SHA-256, SHA-512, and secret-keyed HMAC digests instantly in one place.

Live DNS, SSL & Security Headers Inspector

Inspect any domain’s DNS records, SSL expiration days, and OWASP security headers in real-time.

PDF Password Protect & Unlock

Add strong password protection to confidential PDFs or permanently remove known passwords.