Laboratory temperature control device for controlling the temperature of laboratory samples at a temperature T Target, comprising * a chamber for receiving laboratory samples in the chamber interior, the outer sides of which are formed by at least one chamber wall and a chamber door which closes a chamber opening through which the chamber interior is accessible to the user, * a temperature control device for controlling the temperature of the chamber, which is mounted in thermal contact with an outer side of the chamber, * a temperature sensor, which is mounted in thermal contact with an outer side of the chamber to detect a temperature T ak, * an insulating device which thermally insulates the temperature control device, the temperature sensor and the chamber from the environment, and * an electrical control device, which is set up to regulate the temperature T ak by means of the temperature sensor and the temperature control device to a setpoint temperature with the value T x0, which is predetermined in such a way that the setting of the temperature T K in the chamber interior to T x0 = T Target results from the temperature regulation T K = T Target, wherein the temperature control device is operated with the electrical power P temp (t) during the temperature control T ak = T x0 as a function of the time t, and the electrical control device detects this power P temp (t) and the time-dependent measured value T ak (t) and the electrical control device comprises a data processing device which is set up to calculate a temperature T Kb as the temperature of the chamber interior as a function of the power P temp (t) and the measured temperature T ak (t). * a chamber for receiving laboratory samples in the chamber interior, the outer sides of which are formed by at least one chamber wall and a chamber door which closes a chamber opening through which the chamber interior is accessible to the user, * a temperature control device for controlling the temperature of the chamber, which is mounted in thermal contact with an outer side of the chamber, * a temperature sensor, which is mounted in thermal contact with an outer side of the chamber to detect a temperature T ak, * an insulating device which thermally insulates the temperature control device, the temperature sensor and the chamber from the environment, and * an electrical control device, which is set up to regulate the temperature T ak by means of the temperature sensor and the temperature control device to a setpoint temperature with the value T x0, which is predetermined in such a way that the setting of the temperature T K in the chamber interior to T x0 = T Target results from the temperature regulation T K = T Target, wherein the temperature control device is operated with the electrical power P temp (t) during the temperature control T ak = T x0 as a function of the time t, and the electrical control device detects this power P temp (t) and the time-dependent measured value T ak (t) and the electrical control device comprises a data processing device which is set up to calculate a temperature T Kb as the temperature of the chamber interior as a function of the power P temp (t) and the measured temperature T ak (t).