title: How to calculate month deadline in php
body: <p>I'm working on a system that allow the user to set the number of month for their own duration as the deadline for their project. The problem I'm facing now is how do I calculate their duration starting from the day they submitted their project to its deadline.</p>
  <p>This is the input where the user can set their month duration:</p>
  <pre><code>&lt;label&gt;Duration:&lt;/label&gt;
  &lt;input type=&quot;number&quot; name=&quot;duration&quot; placeholder=&quot;Number of months&quot; required=&quot;&quot;&gt;
  </code></pre>
  <p>This is what I wanted to do just to make it clear:</p>
  <p>*Let's say the user set 9 month on duration input.</p>
  <p>*And since today is september 2021 as I posted this problem. The start of the project will be this month, and the deadline will be on 2022 June.</p>
  <p>I already searched something about this and I can't find the right solution or maybe I just don't know the right keyword to search for.</p>