A cooktop can include a top plate glass configured to support placement of a cooking container; a memory configured to store a plurality of regression models indicating a relationship between a temperature of the top plate glass and a cooking temperature of the cooking container; a temperature sensor configured to sense the temperature of the top plate glass when operating in a heating mode and output a sensing value; and a processor. Also, the processor can be configured to select a regression model from among the plurality of regression models based on the sensing value of the temperature sensor, and calculate the cooking temperature of the cooking container based on the regression model.