Protect PDF
使用密码和 AES 加密锁定 PDF，以便只有您信任的人才能打开它。
Select PDF files
or drag and drop files here
Got a password-protected PDF? Unlock it here first
How to Protect PDF with Password
1
Upload your document
Select the sensitive PDF you need to lock down.
2
Set a strong password
Type in a secure password. Make sure you memorize it or store it safely!
3
Download encrypted file
We apply military-grade encryption. Now, nobody can view the file's contents without knowing the password.
Frequently Asked Questions
How secure is the encryption used?▼
We use standard AES (Advanced Encryption Standard) encryption, the same cryptographic standard banks and governments rely on to protect sensitive data.
如果我忘记密码会怎样？▼
如果没有它，该文件将永久无法读取。我们不会保留您的密码或文档的副本，因此我们无法为您恢复它 - 将其存储在安全的地方。
密码保护是否也会阻止人们打印或复印？▼
Setting an open password requires anyone to enter it before they can view the file at all, which covers printing and copying too, since they can't access the content without opening it first.
Can I remove the password later if I no longer need it?▼
是的，只要文件不再需要受到限制，就可以使用“解锁 PDF”并输入密码将其取消。
当我设置密码时，我的密码是否会发送到任何地方？▼
No, the encryption is applied entirely inside your browser, so the password you type never leaves your device.