BMR (Basal Metabolic Rate), or basal metabolism, is the amount of energy (expressed in calories) your body needs to maintain basic functions at rest. These basic functions include breathing, circulation, cell production, nutrient processing, protein synthesis, and ion balance. In other words, it is the energy your body uses to function while you are in a state of rest and not actively engaged in any activity.

Calculating your BMR can help determine your daily caloric needs, especially if you want to lose weight, gain weight, or maintain your current weight.