Your can follow one of these methods mentioned below to verify which version of Salesforce your company is on.
Method 1:
Log into Salesforce from a web browser and hover your mouse over the Salesforce tab. The edition of Salesforce will display over the tab.
Method 2:
1. From the Salesforce Administrator Account homepage, click on: User's Name > Setup.
2. On the left hand side of the Setup page, click on: Administration Setup.
3. After clicking on Administration Setup, the Salesforce edition will appear within the middle section.
Method 3:
1. From the Salesforce Administrator Account homepage, click on: User's Name > Setup -> Administrative Setup -> Company Profile Information
2. You will find 'Organization Edition' field that displays the Salesforce Edition