In California there are 16 different climate zones as defined in the California Energy code (Title 24). The code requires slightly different types of buildings in each zone. These different building code requirements make it important for architects, builders, contractors, and homeowners to understand the resources of their unique local climate and how it will influence the performance of their buildings. The objective of this project is to create a tool called Climate Consultant 4.0 that adds a number of features to those in the prior version 3.0, including new graphic screens such as a Monthly Diurnal Averages plot. It also calculates a set of the Top 20 Design Guidelines based on your unique climate, and displays a sketch illustrating how each applies. A new dynamic graphic tutorial has been created to explain the Psychrometric Chart, and how the relationship between air temperature and humidity influences human thermal comfort and HVAC systems design. Climate Consultant 4.0 helps people who are designing, building, and maintaining buildings throughout the world to understand their local climate and how it impacts their building’s energy consumption.