SEERSeerKits

Password Protect PDF Online

Add a password to restrict opening or editing sensitive PDFs. Secure server processing for strong encryption — free for files under 50 MB.

Server Processing

Drag and drop your file here

or click to browse from your device

pdf

Maximum file size: 50 MB

Import fromOneDrive URLs supported

Supported Formats

File types you can use with Protect PDF.

Supported Input Formats

pdf

Available Output Formats

pdf

Usage Limits

Free tier limits for Protect PDF on the web.

  • Max file size

    50 MB per file

  • Daily free uses

    5 conversions per day

  • Batch limit

    Up to 1 file at once

Need more? Try the Seer app for expanded limits.

Privacy & Processing

Bạn cũng có thể thích

Unlock PDF
Remove a known password from PDF files you own. Use only on documents you have legal rights to access — free for files under 50 MB.
Mở công cụ →
PDF Máy Nén
Thu nhỏ kích thước tệp PDF cho email và tải lên bằng cách tối ưu hóa hình ảnh và luồng. Nén cục bộ nếu được hỗ trợ - cấp miễn phí cho các tài liệu dưới 50 MB.
Mở công cụ →
PDF Sáp nhập
Kết hợp nhiều PDF vào một tài liệu theo thứ tự bạn sắp xếp. Việc hợp nhất cục bộ giúp giữ lại các hợp đồng và báo cáo khỏi bộ nhớ của bên thứ ba — miễn phí đối với các tệp nhỏ.
Mở công cụ →

Cách sử dụng

How to password protect a PDF with SeerKits

  1. 1

    Upload your PDF

    Select the document you want to encrypt.

  2. 2

    Enter a strong password

    Choose a password you will remember and confirm it before processing.

  3. 3

    Download protected PDF

    Save the encrypted file. Recipients need the password to open it.

Need more power?

Take Protect PDF further with Seer PDF

The web tool is perfect for quick jobs. When you need bigger files, batch workflows, or pro-grade controls, continue in the Seer app ecosystem — same privacy-first approach, more headroom.

  • Larger file limits beyond the web free tier
  • Batch processing for multiple files at once
  • Advanced codec and quality options
  • Offline processing when you need it on the go
Download Seer PDF

Câu hỏi thường gặp

What type of encryption is used?
SeerKits applies industry-standard PDF encryption compatible with Adobe Acrobat and major PDF readers. Full AES-256 protection is available via Seer Pro.
Can I set separate passwords for opening and editing?
The web tool sets an open password by default. Owner passwords that restrict printing or copying unlock in Seer PDF on desktop.
What if I forget the password?
Passwords cannot be recovered if lost. Store your password securely before encrypting, and keep an unencrypted backup when possible.