An image sensor which relates to a technology for estimating crosstalk of each pixel is disclosed. The image sensor includes a pixel array including a plurality of unit test patterns, each of which is used to measure values of crosstalk components of a plurality of light blocking pixels generated by a single open pixel, the light blocking pixels and the single open pixel included in the unit test pattern, a storage circuit configured to store the measured values of the respective unit test patterns, a calculation circuit configured to calculate a crosstalk value about each target pixel included in the pixel array by combining the stored values, and a correction circuit configured to correct pixel data of the target pixel by reflecting the calculated crosstalk value in the pixel data.