If you have a requirement to just do a single field validation, instead of calling the form validate method which will validate all the fields, then you have to use valid() method on the element

For example if your form has field

to validate only username field, use code

jQuery(‘#username’).valid() But of course you have to link the jQuery validator plugin with your form before you call this method

Related Stack overflow post link here - http://stackoverflow.com/questions/1378472/jquery-validate-can-i-re-validate-a-group-of-fields-after-changing-one