Site Help ID Your Mac
In a different tab or window, go to Apple's Online Check Coverage (https://checkcoverage.apple.com) and enter your serial number (etched onto lower case). What information is displayed below the picture?
MacBook Pro 13" (Retina, Late 2013)
MacBook Pro 13" (Retina, Mid 2014)
MacBook Pro 13" (Retina, Early 2015)