What it does
Adds password protection to a PDF file. The resulting PDF is encrypted and cannot be opened without the password.
Inputs and limits
- Input: a single PDF file.
- Maximum file size: 32 MB (as stated on the web page).
- The password is a plain‑text string entered by the user.
Web app
The page asks you to upload a PDF, type a password (instruction: “Type password”, description: “Come up with a password which you want to use.”), and then it returns a password‑protected PDF. The interface is titled “Secure Your PDFs with Easy Password Protection”.
Command line (CLI)
The Documentize LockPdf plugin encrypts a PDF file. Place the PDF in the input folder, set PLUGIN_INPUT_DIR and PLUGIN_OUTPUT_DIR as needed, and run the plugin with the desired password and lock type. Example options: --password, --lock-type FullDocument. The plugin writes the encrypted PDF to the output folder.
# Linux / macOS (needs the .NET 10 runtime and documentize.lic next to the DLL)
export PLUGIN_INPUT_DIR=./work/input
export PLUGIN_OUTPUT_DIR=./work/output
mkdir -p "$PLUGIN_INPUT_DIR/job1"
cp sample.pdf "$PLUGIN_INPUT_DIR/job1/"
dotnet Documentize.LockPdf.dll --task-id job1 --password test123 --lock-type FullDocument
ls "$PLUGIN_OUTPUT_DIR/job1"
# Windows PowerShell
$env:PLUGIN_INPUT_DIR = "$PWD\work\input"
$env:PLUGIN_OUTPUT_DIR = "$PWD\work\output"
New-Item -ItemType Directory -Force "$env:PLUGIN_INPUT_DIR\job1" | Out-Null
Copy-Item sample.pdf "$env:PLUGIN_INPUT_DIR\job1\"
dotnet Documentize.LockPdf.dll --task-id job1 --password test123 --lock-type FullDocument
Get-ChildItem "$env:PLUGIN_OUTPUT_DIR\job1"
Verified
Every code sample on this page was run on 2026-11-03 and its result was checked:
- Lock PDF with Documentize.LockPdf plugin (CLI plugin): passed in 10 s