Protect PDF — Free Online
Add a password to a PDF so only people who know it can open it — useful for contracts, payslips, medical forms and other private documents sent by email.
Server processing — this file is sent to our conversion server and deleted immediately after conversion.
PDFs: max 50 MB and 500 pages per file. Images: max 20 files, 20 MB each. Word files: max 10 MB.
PDF files only.
Your password is sent only for this one encryption, is never stored or logged, and cannot be recovered if you forget it — keep a copy somewhere safe.
How to use Protect PDF
- Choose an unprotected PDF file.
- Enter a password of at least 4 characters and confirm it.
- Process the file and download the protected PDF. Keep the password safe — it cannot be recovered.
Supported files and limits
PDFs: maximum 50 MB and 500 pages per file. Images: maximum 20 files, 20 MB each. Word files: maximum 10 MB, DOCX only. No account is required for any basic tool.
Processing: on our conversion server. The file is deleted immediately after conversion and download, is never stored in a database, and its contents are never logged.
Limitations — stated honestly
- Protection uses standard PDF encryption. Most modern viewers support it, but some older tools and viewers may behave differently.
- A forgotten password cannot be recovered by us — there is no reset, because the password is never stored.
- Protection controls opening the file; it does not stop someone who already knows the password from copying or printing it.
Frequently asked questions
- Can I remove the password later?
- Not with this tool. Keep an unprotected copy if you may need one, and store it safely.
- Is my password stored or logged?
- Never. It is used only for this one encryption and is never stored, logged or sent to analytics.
- Does this work on an already-protected PDF?
- No — start from an unprotected PDF.