Toronto is 92% larger than Atlanta.
Area: 346 km2 calculated
Atlanta is the capital of and the most populous city in the U.S. state of Georgia, with an estimated 2013 population of 447,841. Atlanta is the cultural and economic center of the Atlanta metropolitan area, home to 5,522,942 people and the ninth largest metropolitan area in the United States. Wikipedia
Area: 665 km2 calculated
Toronto is the most populous city in Canada and the provincial capital of Ontario. It is located in Southern Ontario on the northwestern shore of Lake Ontario. The history of Toronto began in the late 18th century when the British Crown purchased its land from the Mississaugas of the New Credit. Wikipedia