Image compensation value computation techniques are described. In one or more implementations, an image key value is calculated, by a computing device, for image data based on values of pixels of the image data. A tuning value is computed by the computing device using the image key value. The tuning value is configured to adjust how the image data is to be measured to compute an image compensation value. The image compensation value is then computed by the computing device such that a statistic computed in accordance with the tuning value approaches a target value. The image compensation value is applied by the computing device to adjust the image data.