According to an embodiment, a data converting device is connected to a power meter configured to add up power consumptions of electrical equipment. The device includes a receiving unit configured to receive power consumptions per predetermined unit time added up by the power meter; and a calculating unit configured to calculate a second sequence to be stored as added up power consumptions in a storage unit from a first sequence containing the power consumptions per unit time received by the receiving unit in time series by using a conversion rule for converting a value of a second element in the second sequence based on a value of a first element in the first sequence. The second sequence has no privacy information and, the second sequence can be used for calculating a total value of the first sequence.