A display apparatus including a classifier configured to classify image data into preset data of an n-bits (“n” is a natural number), a toggle counter configured to count a number of toggles based on preset data of a present horizontal line and a previous horizontal line and to calculate a final toggle number using a weighted values corresponding to a swing width between data voltages of the present and previous horizontal lines, a determiner configured to determine a representative toggle number of a present frame based on a plurality of final toggle numbers of the present frame, compare the representative toggle number with a plurality of threshold values and determine a level of a power control signal based on a compared result.