The NRC Calculator estimates energy and protein allowable average daily gain of the dairy calf based on user inputs regarding the volume of whole milk and/or milk replacer fed, the percent solids of whole milk or milk replacer solution, whole milk protein, and fat content, milk replacer protein, fat, moisture and ash content, starter grain intake, protein content, and metabolizable energy content, calf body weight, and ambient temperature. Milk replacer, whole milk, or a combination can be analyzed and two strategies can be compared side-by-side on one convenient screen. The calculator reports energy allowable average daily gain and protein allowable average daily gain for each diet thus enabling an easy assessment of the constraint to an increase in potential calf body weight gain. Measurements are available in metric or imperial, and the program is operable in English, Spanish, Portuguese, French, Chinese, and Japanese. This app is available for free globally on a variety of platforms. All formulas are based on Nutrient Requirements of Dairy Cattle, Seventh Revised Edition, 2001, subcommittee on Dairy Cattle Nutrition Board and Natural Resources National Research Council (NRC), National Academy Press, Washington, D.C., U.S.A. The NRC Calculator is a joint project between Milk Products Inc, and Animix LLC of Juneau, Wisconsin.