Get the current date and the date 30 days ago. Then format the dates like this: M/D/YYYY. This an example of date manipulation in JavaScript.

dateRange.js

/**
 * Get the current date and the date 30 days ago.
 * Then format the dates like this: M/D/YYYY.
 */

var diff = 2592000000;
var now = new Date();
var diffDate = new Date( now.getTime() - diff );
var nowPrint = [ now.getMonth() + 1, now.getDate(), now.getFullYear() ].join("/");
var diffPrint = [ diffDate.getMonth() + 1, diffDate.getDate(), diffDate.getFullYear() ].join("/");