messages Object

Set of messages (either strings or functions) which will be shown when given validation rule fails. By setting already existing key the appropriate built-in message will be overridden.

Defining custom messages

<form id="myform">
    <input name="username" required /> <br />
    <input type="email" name="userEmail" required data-message="My custom email message" /> <br />

         messages: {
             // defines a message for the 'custom' validation rule
             custom: "Please enter valid value for my custom rule",

             // overrides the built-in message for the required rule
             required: "My custom required message",

             // overrides the built-in message for the email rule
             // with a custom function that returns the actual message
             email: function(input) {
                 return getMessage(input);
         rules: {
           custom: function(input) {
             if ("[name=username]")) {
                 return input.val() === "Tom";
             return true;

    function getMessage(input) {
In this article