To determine what version of any iZotope plug-in you have installed, start by opening your host application and instantiating the plug-in. Next, open the Settings menu by clicking the gear icon. You’ll see the version number of your plug-in here in the settings menu. This method will also work for Ozone standalone applications.
For RX standalone applications, you can find your version number by launching the software and accessing the “About” screen. In Windows this can be found under “Help”. On a Mac it is located under “iZotope RX” in the menu bar.
If there is any question as to whether or not you have the most recent version installed, log in to view and download installers for every current product you own. Legacy product installers can be found under “Legacy Products” on that same page.