momentjs convert datetime to UTC from another timezone
<p>I'm having dates like the below:</p>

<p><strong>05/30/2014 11:21:37 AM</strong></p>

<p>My users will be entering in that data and having their own timezone. It could be anything like "US/Eastern", "US/Pacific-New", etc. I want to convert the time to UTC but i'm not able to. Is there a way to do so?</p>

<p>I'm using node and I tried momentJS and read the below:</p>

<p><a href="http://momentjs.com/docs/" rel="noreferrer">http://momentjs.com/docs/</a></p>

<p><a href="http://momentjs.com/guides/" rel="noreferrer">http://momentjs.com/guides/</a></p>

<p><a href="https://stackoverflow.com/questions/10087819/convert-date-to-another-timezone-in-javascript">Convert date to another timezone in JavaScript</a></p>

<p>How do I convert from a different timezone to UTC?</p>

<p><strong>Edit</strong></p>

<p>I have tried these:</p>

<pre><code>moment().utc(0).format('YYYY-MM-DD HH:mm Z')
moment.tz(dateString, "US/Eastern").format()
</code></pre>

<p>In the above example <code>dateString</code> is the string date. I want to set the timezone to "US/Eastern" and convert it to UTC.</p>