A weighing apparatus for weighing a mass of an object is provided with: a body; a load receiving device, a load detection device, an acting force detection device, and a data processing device configured to data-process an output of the load detection device as a weighed value in a mass unit. The data processing device has: a load output acquisition unit configured to acquire an output of the load detection device; a force output acquisition unit configured to acquire an output of the acting force detection device; and a correction coefficient calculation unit configured to calculate, as a correction coefficient for correcting an output of the load detection device, a change amount of an output of the load output acquisition unit with respect to a change amount of an output of the acting force detection device based on (i) outputs of the load detection device and the acting force detection device acquired respectively by the load output acquisition unit and the force output acquisition unit, when the weighing apparatus with zero load applied thereto is placed in a first attitude and (ii) outputs of the load detection device and the acting force detection device acquired respectively by the load output acquisition unit and the force output acquisition unit, when the weighing apparatus with zero load applied thereto is placed in a second attitude, which differs from the first attitude.