There are many different gear rating methods in use today, and they can give substantially different results for any given gearset. This paper will make it easy to understand the choices and the impact the choices have on gearbox design. Eight standards are included - AGMA 2001; AGMA 6011; AGMA 6013; ISO 6336; API 613; API 617; API 672; and API 677. (Click HERE for the Appendix to this article).