Google Chrome:
While in a browser window, click on the three dots in the upper right corner.
This opens a menu. Go down to Help and click.
The first option is About Google Chrome
Then you should see a screen similar to this.
You will see the version number and then in parenthesis, 64-bit or 32-bit.
Firefox
Click the menu button 
, click and select . The About Firefox window will appear. The version number is listed underneath the Firefox name, and next to that it will show you 64-bit or 32-bit.
Here is an example of what the About Firefox window will look like:
Note: Opening the About Firefox window will, by default, start an update check. If an updated version of Firefox is available, it will be automatically downloaded.
- Alternatively, click the menu button , click and select . A page with the address about:support will appear in a new tab. Your Firefox version is listed underneath the Application Basics section of the page. For more information, see Use the Troubleshooting Information page to help fix Firefox issues.