A measuring device for the determination of at least one thermal property of a fluid, for example, the volumetric heat capacity and the thermal conductivity, wherein the measuring device includes a thermal property sensor and an evaluation unit, wherein the evaluation unit is adapted to determine the thermal property from a measurement signal determined by the thermal property sensor, wherein the thermal property sensor includes a heater, a first temperature sensor and a second temperature sensor, wherein the thermal property sensor includes a mounting plate with an opening, wherein the heater, the first temperature sensor and the second temperature sensor are arranged above or inside the opening.