Password Protect PDF Files
Secure your PDF documents with password protection. Prevent unauthorized access and control document permissions with encryption.
More information about this conversion
From simple conversions to a more complex automation using workflows, PDFengine provides professional-grade tools for every PDF task.
Strong Encryption
Choose either 40, 128, or 256-bit, industry-standard security to protect sensitive documents. Set both user password (for viewing) and owner password (for editing).
Batch Protection
Apply the same security settings to multiple PDF files simultaneously. Efficient protection for document collections.
Even greater efficiency with PDFengine workflows
Take document management to the next level by combining and sequencing PDF conversion, optimalization, and/or organization tools. With fully customizable workflows, complicated PDF tasks cost just seconds to complete.
Why choose us to convert your files
Lightning Fast Conversion
Our advanced conversion engine processes your files in seconds, not minutes. Upload, convert, and download - all within moments.
Focus on business
Archive and convert email, AutoCAD, Visio, and Office files in one streamlined workflow. Perfect for companies with recurring document processes.
Perfect Quality Every Time
Our intelligent algorithms preserve formatting, fonts, images, and layouts. What you see is what you get - no quality loss.
How it works
Process your documents easily and quickly in three steps
Upload PDF Files
Select the PDF documents you want to password protect.
Set Passwords
Enter user password (viewing) and owner password (editing). Choose encryption level.
Download Protected PDFs
Get your password-protected PDF files with strong encryption applied.
Frequently Asked Questions
What is the difference between user and owner passwords?
User password is required to open and view the PDF. Owner password is required to edit, print, or modify the document. You can set both for complete control.
Which encryption level should I choose?
256-bit AES is recommended for maximum security. 128-bit provides good security for most needs. 40-bit is legacy support only.
Can I remove password protection later?
Yes, use our Unlock PDF tool to remove password protection if you know the owner password.
What file size limits apply?
You can process up to 10 PDF files with a total size of 200MB and maximum 1000 pages across all documents.
Why is it handy to convert my document to PDF?
Converting a file to PDF ensures your document stays consistent and accessible. PDFs lock in formatting, design, and structure, preventing layout shifts that can happen with editable file types. They’re compatible with virtually all devices and operating systems, making them ideal for professional documents, forms, reports, and presentations. PDFs are also easy to distribute; whether through email, downloads, cloud platforms, or QR-codes that let users open a file instantly on their phone.
Will documents lose quality when converted?
Our intelligent software minimizes quality loss when converting documents. As such, documents can be converted without having to worry about quality loss for a great number of times.
Will my document lay-out or format be changed if I convert it?
No; our intelligent PDF software recognizes document layouts and transforms them accurately onto a new file format. Was your lay-out or format not transformed accurately? Consider applying OCR, or applying different customization settings to convert it correctly.
Can I convert a document into PDF and convert it back into original format?
Yes! There are no limits to converting documents, and documents can safely and easily be converted back and forth. Conversion can be handy to edit a PDF document in Word, and later convert it back into an organized PDF format.
How can I merge PDF documents?
To merge PDF documents simply go to our converter, choose the file format you’re merging, and drag and drop the files you want to merge. Then you have the opportunity to edit some settings, press merge, and you’re done! You can download your merged file right away.
Can I customize my PDF documents while converting?
Yes, PDFengine offers various means of customizing your (PDF) documents. Consider adding a cover page, applying OCR, or using PDF/A as output.
Why is the text in my PDF not displayed correctly?
If the text is not copyable, clickable, or searchable, that means the text is not recognized within the PDF. Try uploading your document onto PDFen and applying OCR. OCR technology will make your text readable. In case it doesn’t work completely in one go: apply OCR a second time.
Ready to Protect Your PDFs?
Secure your sensitive documents with password protection and encryption.
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