How to check the PHP version in Xampp can be done in the following way:

• Open a text editor (notepad/notepad++)
• Type the following code,

<?php
phpinfo();
?>

• Save (save as) with the name (version.php) in the htdocs directory(Xampp).
  Usually by default the directory is in C:\xampp\htdocs.
  This directory depends on where you installed Xampp the first time.
• Open the browser
• Type: localhost/version.php
• If appropriate, the Php version information will appear as below.