You may be able to access to some different Wi-Fi connections. How to choose the one with the highest internet connection speed?
There will be 2 quick ways to check.
Mac user can simply hold down the Option key while clicking on the menu bar icon for your Airport. This will show-up all information you need.
Check WiFi Speed via the Network Utility
You can either use the Network Utility by using Cmd+Space to pull up the Spotlight search box and typing it in or navigate through your Applications -> Utilities folder to find it.