Abstract: Thermal control devices and methods to provide improved control, speed and efficiency in temperature cycling are provided herein. Such thermal control device and methods can include one or more active elements, such a thermoelectric cooler device, that is controlled by an algorithm that regulates a temperature distribution of an adjacent reaction-vessel according to a temperature distribution command trajectory and estimated reaction-vessel temperature distribution. Some embodiments include two active elements that are bilaterally applied to opposing sides of the reaction-vessel. In some embodiments, the estimated reaction-vessel temperature is determined based on a state of power electronics of the element and a temperature output of one or more sensors of a portion of the element and/or an ambient environment of the reaction-vessel. Methods of calibration of such systems utilizing a thermal calibrator as a proxy for the reaction-vessel are also provided herein.