A field describes a single type of data which you can associate with your contacts. Imagine fields as extra columns of typed data that you can augment the contact’s email address with. Examples might include information on your contacts’ name and address, purchase history, demographics, and the like.


Warning: Do not use fields to store particularly sensitive or private information about your contacts or information requiring stronger controls than provided by the application. Information such as credit card numbers, social security numbers, unencrypted passwords, and other similar data should be stored outside of the application in a system specifically designed for handling this type of data. You are responsible for any consequences of processing any data placed in the application inappropriately.
Any field data you use in a message must be smaller than 1 MB.
Name Type Description
id string The unique id of the field.
name string The internal name of the field.
label string The external (public facing) name of the field.
type string The type of field:
  • text – Text box (max character limit: 65535)
  • textarea – A large multi-line text box (max character limit: 65535)
  • password – A text box that hides typed characters (max character limit: 65535)
  • checkbox – Check boxes (max character limit: 1). Accepts a string value of true or false.
  • radio – Radio buttons. Accepts values that are predefined in the UI or a value that is passed in, if it is not already defined, but it will not be saved as a new option.
  • select – Pull-down menu
  • integer – Accepts any 10-digit, whole number less than or equal to 2147483647. If you need to store a static number (a number that is not incrementing or decrementing), we suggest using either a predefined field, or a custom field with a type of Text. For example, to store telephone numbers use one of the predefined fields created for storing telephone numbers. If you are storing incrementing or decrementing numbers in a custom field created with a type of Number, be mindful of the 10 digit, 2147483647 limit.
  • currency – Accepts any positive or negative number with two decimal points (max character limit: 15)
  • float – Accepts any positive or negative number with a decimal point (max character limit: 53)
  • date – A value that matches a specific date. See dateValue for more information on the date format.
visibility string The visibility selected for the field {public, private}. Public fields are visible to you and can be made visible to your contacts. Private fields are visible only to you.
options fieldOptionObject[] The possible options that can be set for a field if the field is a pull-down, check box, or radio button.