An accurate design wave is critical for a reliable estimation of armor size. In many cases waves are depth limited and the design wave can be calculated using “Breaking Waves”. Using this wave height for design would generally give conservative results for armor size. A more sophisticated approach is to apply an irregular wave transformation model such as that of Goda calculated with the “Irregular Waves” page. This approach requires the user to have some background with regard to deep sea design waves and directionality, implications of wave refraction and assumptions implicit in using Goda’s model. To ensure reliable and optimum designs the use of hydraulic model studies are recommended.