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Bảo vệ mật khẩu
Thêm mã hóa mật khẩu vào PDF để hạn chế truy cập.
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Thả file PDF vào đây
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Câu hỏi thường gặp
How do I add a password to a PDF?expand_more
Upload your PDF, type a password, and click Protect. The output file requires the password to open.
What encryption standard is used?expand_more
AES-256, the same encryption standard used by banks and government agencies.
Is my password stored anywhere?expand_more
No. The encryption happens in your browser and the password is never transmitted or stored. If you forget it, it cannot be recovered.
Can I set separate owner and user passwords?expand_more
Yes. The user password controls who can open the file, while the owner password controls who can edit, print, or copy content.