To check the unique Wireless Local Area Network (WLAN) Media Access Control (MAC) address that identifies your Nokia phone, enter *#62209526# press call (in the idle mode) or with touch screen phones after opening the dialler.
If the above mentioned code does not work on your phone (like in the Asha series) then
check the label on the phone box, if it has WLAN mentioned, it will mention the
MAC address of your phone.