is-iso-date 
is-iso-date is a simple utility to check if a string is an ISO-compliant date.
Install
$ npm install is-iso-date
Usage
var isISODate = require( 'is-iso-date' );
console.log( isISODate( '2015-02-21T00:52:43.822Z' ) ); // true
console.log( isISODate( '2015-02-21T00:52:43.822' ) ); // false
console.log( isISODate( '2015-02-21T00:52:43Z' ) ); // true
console.log( isISODate( '2015-02-21T00:52:43' ) ); // false
console.log( isISODate( '2015-02-21T00:52Z' ) ); // true
console.log( isISODate( '2015-02-21T00:52' ) ); // false
console.log( isISODate( '2015-02-21T00Z' ) ); // falseReference
This is basically just the regexp from this StackOverflow discussion wrapped in a tiny library with some tests: http://stackoverflow.com/questions/3143070/javascript-regex-iso-datetime