How to find Joomla version
There are multiple ways to find out the version of your Joomla instance. The easiest way to find it would be through your Joomla’s dashboard.
First of course, you would need to be logged into your Joomla’s administrator dashboard. In case it has not been changed, the login URL should be yourdomain.com/administrator, where you will be asked to fill in your administrator Username and Password.
Once logged into your Joomla dashboard, select “System” from the menu on the top of your screen and click “System Information” from the drop-down. The System Information page contains all the information you may need for the Joomla version currently running, as well as the server type, PHP and database versions, etc.
The Joomla version is also being displayed at the bottom right corner of every page in your Joomla’s dashboard.
In case you do not have access to the Joomla dashboard, but you can access the website’s files, you may check the version there. To do that, you should go to the root folder of your Joomla website, where you need to open the “libraries” directory and in the “scr” folder you will find the file “Version.php”, where the Joomla version can be found.
If however, the version of your Joomla website is lower than 3.8.x, then the version.php file will be located in the root folder of your Joomla website → libraries → cms → version.