Mexico City is located in Mexico.
Greater Mexico City . Starting 2016 , On January 29 , Mexico City proper ceased to be called the Federal District ( Spanish : `` Distrito Federal '' or D.F. ) and is now in transition to become the country 's 32nd federal entity called officially `` City of Mexico '' ( Spanish : `` Ciudad de Mexico '' or CDMX ) , giving it a level of autonomy comparable to that of a state . Mexico City . According to the most recent definition agreed upon by the federal and state governments , the Greater Mexico City population is 21.2 million people , making it the second-largest metropolitan area of the western hemisphere , behind New York City , the tenth-largest agglomeration , and the largest Spanish-speaking city in the world .