A display device includes a display divided into a plurality of blocks including pixels, a timing controller for calculating a frame load for an image frame of input image data, and for generating image data by scaling grayscale values of the input image data using a scale factor, a data driver for generating a data signal corresponding to the image data, and for supplying the data signal to the pixels, a current sensor for sensing a global current flowing in a first power source line connected to the pixels, and a scale factor provider for correcting a unit target current determined using a reference block among the blocks based on a deviation in light emitting characteristics between the blocks, for calculating a target current using the frame load and a corrected unit target current, and for comparing the target current with the global current to calculate the scale factor.