Password Protect PDF — Add Security
Add password protection to PDF files. Secure sensitive documents.
200万+文件已转换
数千用户的信赖之选
安全传输
HTTPS 加密上传
隐私优先
文件处理后自动删除
无需注册
即刻开始转换
随处可用
任何浏览器,任何设备
如何转换
Upload your PDF file.
Set a password and choose restriction options.
Click Protect and download your secured PDF.
About Protect PDF
Protecting sensitive PDF documents with passwords is essential for maintaining confidentiality when sharing files via email, cloud storage, or other channels. Our PDF protection tool adds industry-standard encryption to your documents, ensuring only authorized recipients can access the content.
PDF security offers two levels of protection that can be used independently or together. An open password (also called user password) prevents anyone from viewing the document without entering the correct password first. A permissions password (owner password) allows viewing but restricts specific actions like editing, printing, or copying text. This dual-layer approach lets you share viewable documents while preventing unauthorized modifications.
Financial professionals protect sensitive client reports, tax documents, and investment summaries before transmission. Healthcare providers encrypt patient records and medical reports to maintain HIPAA compliance. Legal teams secure confidential contracts, settlements, and client communications. HR departments protect employee records, salary information, and performance reviews when sharing with authorized personnel.
Our encryption uses 256-bit AES, the same standard employed by banks, governments, and military organizations worldwide. This level of encryption is considered virtually unbreakable with current technology. The protected PDF works with all standard PDF readers including Adobe Acrobat, Preview, and web browsers, which will prompt for the password before displaying content.
Common Use Cases
- •Secure confidential business documents before email transmission
- •Protect financial statements and tax documents
- •Encrypt medical records for HIPAA compliance
- •Secure contracts and legal documents
- •Protect intellectual property and proprietary information
How It Works
Our PDF protection uses QPDF with AES-256 encryption, the strongest encryption available for PDF documents. The tool supports both user passwords (for opening) and owner passwords (for permissions). All PDF 2.0 permission flags are available including print, copy, edit, and form fill restrictions.