Random wave-induced pore pressure is examined using linear superposition, Miner’s method and a single representative wave. Solutions are developed for deep and shallow soils. A deep soil has a higher liquefaction potential than a shallow soil for the same wave conditions. Linear superposition, Miner’s method and using the rms wave height are in general agreement for the deep soil. The significant wave overestimates the liquefaction potential and should not be used. There was poor agreement among the methods for a shallow soil.