Password Protect PDF

Updated:

About to send a PDF with sensitive details and want it locked? This free Password Protect PDF tool secures it fast. Upload the file, set a password, and download an encrypted PDF only the right people can open. Worth it when things are sensitive:

  • Lock a contract before emailing it
  • Secure payroll or financial documents
  • Protect client records in transit
  • Add a password to a confidential report

A Quick Word on IronPDF

IronPDF is the C# PDF library trusted by thousands of .NET developers in production. It encrypts PDFs and sets open or permission passwords from code, with control over printing, copying, and editing rights.

using IronPdf;
var pdf = PdfDocument.FromFile("document.pdf");
pdf.SecuritySettings.UserPassword = "secret123";
pdf.SaveAs("protected.pdf");
using IronPdf;
var pdf = PdfDocument.FromFile("document.pdf");
pdf.SecuritySettings.UserPassword = "secret123";
pdf.SaveAs("protected.pdf");
Imports IronPdf

Dim pdf = PdfDocument.FromFile("document.pdf")
pdf.SecuritySettings.UserPassword = "secret123"
pdf.SaveAs("protected.pdf")
$vbLabelText   $csharpLabel

See it in C#: Passwords & permissions guide

Free and Built for Everyday Use

This tool is completely free and made for quick, practical use, no signup, no limits, no catch. Built with love by IronPDF.

Need More Than PDFs?

When the project grows beyond PDF work, the Iron Suite bundles ten .NET libraries into a single license: IronOCR for reading text from images in 125 languages, IronBarcode for generating and scanning codes, plus IronXL, IronWord, IronPPT, and more. Start your 30-day Iron Suite trial key today, no credit card required.