SECURITY · PROTECT
Protect PDF
Keep your sensitive documents safe by locking them with a highly secure, unbreakable password — free, unlimited, and 100% private.
Files are processed on your device — nothing is uploaded.
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How it works
01
Upload Document
Drag and drop the PDF you want to protect into the box.
02
Set a Password
Type a strong password to lock your file. Make sure you don't forget it!
03
Encrypt & Save
Click protect and download your newly encrypted PDF document.
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Frequently asked questions
Can you recover my password if I forget it?
No. The encryption happens on your device and we do not store your passwords. If you lose your password, the file cannot be opened.
How strong is the encryption?
We use industry-standard AES encryption to guarantee that your file cannot be brute-forced easily.
Why do my PDFs load or process slowly?
Since there is no server involved, all processing speed depends entirely on your computer and browser's hardware. Large files may take longer on older devices or if your browser is under heavy load.
Is there a file size or page limit?
No fixed limits. Because your own device does the work, even documents with hundreds of pages are processed without running out of memory. Very large jobs simply take longer.
What happens with password-protected or damaged PDFs?
Password-protected PDF files cannot be processed by other tools until their password is removed. You can first use our free "Unlock PDF" tool on this website to remove the password with 100% privacy, and then freely use your unlocked file across any of our tools. Corrupted or unreadable PDF files are safely skipped with a clear error message.
Do I need an internet connection to use the tools?
You only need an internet connection to load the website initially. Once the page is loaded, the tools work entirely offline because all the processing happens directly inside your browser.
Is there a limit on how many files I can process per day?
Absolutely no limits. Since your own device is doing the processing, there are no server costs, meaning you can convert, merge, or split as many documents as you want, completely free forever.
Does the quality of my PDF decrease after processing?
No. We use high-quality rendering engines. For image conversions, you can even select the exact DPI (up to 300 for print quality) to ensure no loss of detail. Merging and splitting operations preserve the original document quality perfectly.