Computing the integral nonlinearity (INL) of an ADC from the histogram of output codes for a sine wave input is investigated. Two algorithms are compared: one based on a proposal by Doernberg et al. (1984) and another based on a proposal by van Bossche et al. (1986). Doernberg's algorithm has evolved into a quasi industry standard Burns, M et al. (2001) while van Bossche's algorithm has been standardized by the IEEE. Simulating the test method of sinewave histogramming for a perfectly linear ADC, both computation algorithms yield comparable results; in the presence of ADC nonlinearities results, however, they differ. This questions the suitability of the two algorithms for the purposes of testing the worst-case non-linearity specifications for ADCs.