The durability of galvanizing estimator interpolates between corrosivity category distances in AS 4312 to determine the corrosivity of the location. The estimated lives to first maintenance of galvanizing and duplex systems are found using interpolation of AS/NZS 2312.2, and the estimated life to first maintenance of paint only systems are found using interpolation of AS 2312.1. A tool for estimating the life of other galvanized coatings is also provided based on the coating thickness provided in their standards. Many design, site specific or environmental factors can effect the corrosion rate and life to first maintenance of a coating system. These include sheltering from rain washing which will increase the expected rate of corrosion, while sheltering from the surf by islands, topography or buildings decreases the expected rate of corrosion. This tool is meant to provide an estimation only for articles batch hot dip galvanized to AS/NZS 4680, and a detailed site inspection and professional advice should be sought from a coatings professional before choosing a protective coating method.