Authentication

Obtain your API key

The Email API client requires a single credential:

API key: a secret token that authenticates your requests

It is available in the Paubox dashboard under API Credentials.

Option 1: Constructor parameter

Pass your API key directly; useful for console apps or when managing secrets via environment variables:

var emailLib = new EmailLibrary("YOUR_API_KEY");

Read from an environment variable:

var emailLib = new EmailLibrary(
    Environment.GetEnvironmentVariable("PAUBOX_API_KEY")
);

Option 2: IConfiguration (recommended for ASP.NET Core)

Add your API key to appsettings.json:

{
  "APIKey": "YOUR_API_KEY"
}

Then inject IConfiguration and pass it to the constructor:

// In Program.cs or Startup.cs
builder.Services.AddSingleton<IEmailLibrary>(sp =>
{
    var config = sp.GetRequiredService<IConfiguration>();
    return new EmailLibrary(config);
});

Or instantiate directly:

var emailLib = new EmailLibrary(configuration);

The SDK reads APIKey from the configuration and sets the Authorization header automatically on every request:

Authorization: Token token=YOUR_API_KEY

Forms client

FormsLibrary requires no credentials. Instantiate it with no arguments:

var formsLib = new FormsLibrary();

Use IFormsLibrary in ASP.NET Core for dependency injection and testability:

builder.Services.AddSingleton<IFormsLibrary, FormsLibrary>();

Security notes

Never hard-code credentials in source files. Use appsettings.json with user secrets or environment variables.
Use .NET user secrets during development to keep credentials out of source control.

Get started

Email API

Migrate to Paubox

Marketing API

MCP Server

SDKs

CLI

Forms API

Obtain your API key

Option 1: Constructor parameter

Option 2: IConfiguration (recommended for ASP.NET Core)

Forms client

Security notes

​Obtain your API key

​Option 1: Constructor parameter

​Option 2: IConfiguration (recommended for ASP.NET Core)

​Forms client

​Security notes

Obtain your API key

Option 1: Constructor parameter

Option 2: IConfiguration (recommended for ASP.NET Core)

Forms client

Security notes