Ironpdf License Key

After setting the key, you can verify that it is working:

bool isValid = IronPdf.License.IsValidLicense;
Console.WriteLine($"License valid: isValid");
string licenseType = IronPdf.License.LicenseType;
Console.WriteLine($"License type: licenseType");

Also, generate a simple PDF and check for the absence of the red watermark:

var renderer = new ChromePdfRenderer();
var pdf = renderer.RenderHtmlAsPdf("<h1>Test License</h1>");
pdf.SaveAs("test.pdf");

If the watermark is gone, the license is correctly applied. ironpdf license key

Store keys in secrets manager, not source control.

✅ Good:

License.LicenseKey = Environment.GetEnvironmentVariable("IRONPDF_KEY");

❌ Bad:

License.LicenseKey = "abc123-xyz"; // Hardcoded

IronPDF binds evaluation keys to a specific machine fingerprint. If you change hardware (RAM, CPU, Disk) or clone a VM, the key breaks. Solution: Log into the Iron Software portal and "deactivate" the old machine to release the license lock, or purchase a key that supports floating licenses. After setting the key, you can verify that