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保护PDF

protector.subtitle

上传要保护的PDF
或点击浏览
最大100MB 安全
保护设置
PDF
-
-
为了最佳安全性，请使用至少8个字符，包括大小写字母、数字和符号
密码生成器
16
文档权限
保护完成！
您的PDF已使用密码加密保护。

使用方法

1

Upload your PDF

上传您的PDF文档

2

Set the password

设置安全密码

3

Configure permissions

配置文档权限

4

Download protected PDF

下载受保护的PDF

✓

继续使用工作流程

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Workflow 当前步骤: 1

Password Protect PDF Files Online Free

Add password protection and encryption to your PDF documents. Restrict printing, copying, and editing permissions. Secure sensitive documents with strong AES encryption without installing any software.

How to Password Protect a PDF

  1. Upload the PDF file you want to protect
  2. Set your password and choose which permissions to restrict
  3. Download the encrypted PDF file

常见问题

What's the difference between open and permission passwords?

The open password is required to view the document. The permission password controls what actions (print, copy, edit) are allowed.

How strong is the encryption?

We use AES 256-bit encryption, the same standard used by banks and government agencies.

Can I protect multiple files at once?

You can process files one at a time. Each file can have its own unique password and permission settings.

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PDF-Ninja Gmail版 - Chrome扩展

直接在PDF-Ninja中打开Gmail的PDF附件。即时编辑、签名和转换您的PDF！

免费安装扩展

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