A liquid crystal display includes a display panel, a timing controller, a gate driver, and a data driver. The display panel includes a plurality of pixels. The timing controller receives an image data, compares a previous line data with a present line data to determine whether the present line data needs to be compensated, and generates a first modulation line data. In addition, the timing controller calculates the first modulation data and a delay compensation value to generate a second modulation line data. The delay compensation value is decided from reference delay compensation values of reference pixels among the pixels.