A display device includes a display panel having a plurality of pixels, a plurality of sensing units formed in row and column directions in the display panel, each of the sensing units generating a first sense data signal based on a contact on the display panel, a sense signal processor generating second sense data signals based on the first sense data signals, and a contact determiner generating first deviation data based on the second sense data signal of a predetermined frame and the second sense data of a sample frame group, in the second sense data signals with respect to a predetermined sensing unit of the second sense data signals in a plurality of frames, generating second deviation data based on the first deviation data of a predetermined sensing unit and the first deviation data of a sample sensing unit, in the first deviation data of a predetermined frame, and determining whether a contact occurs and a contact position based on the second deviation data.