How to properly format last modified (lastmod) time for xml sitemaps

Question

I am creating an app that will automatically update sitemap.xml each time new content is added to, or updated on the site.

According to Google\'s best pract

Answer 1

In PHP, you can use :

$lastmod = date("Y-m-d\Th:m:s+00:00");

This will display something like:

2018-02-14T08:02:28+00:00