Abstract: A precision balance including a weighing chamber (16), a draft shield (18, 20, 22) which surrounds the weighing chamber, a climate module (34) which is detachably disposed in the weighing chamber, a processor (32), a data input unit, and a data transmission path over which data is exchanged between the climate module and the processor. The processor has a measurement uncertainty determining module (33) with which the measurement uncertainty of the balance is determined. Also disclosed are a method for determining a measurement uncertainty of a balance and a climate module 4 that forms a self-contained modular unit, and includes an air pressure sensor (62), an air humidity sensor (54) and an air temperature sensor (52). A data transmission path transmits data to a processor external to the climate module.