A circuit device includes an oscillation circuit that generates an oscillation signal by using a vibrator, a frequency adjustment circuit that adjusts an oscillation frequency of the oscillation circuit based on frequency adjustment data, a temperature sensor circuit that outputs temperature data, an arithmetic operation circuit, and a storage circuit. The arithmetic operation circuit outputs converted temperature data by performing, on the temperature data, conversion processing in which a slope of the converted temperature data with respect to the temperature data in a first temperature range is different from a slope of the converted temperature data with respect to the temperature data in a second temperature range. The storage circuit stores a lookup table representing a correspondence between the converted temperature data and the frequency adjustment data.