A simple Base64 Encode and Decode Example in C#/CSharp.   Base64 Encode Example in C# public static string Base64Encode(string plainText) { var plainTextBytes = System.Text.Encoding.UTF8.GetBytes(plainText); return System.Convert.ToBase64String(plainTextBytes); }     Base64 Decode Example in C# public static string Base64Decode(string base64EncodedData) { var base64EncodedBytes = System.Convert.FromBase64String(base64EncodedData); return System.Text.Encoding.UTF8.GetString(base64EncodedBytes); }