What is the difference between BMI and BMR?

BMI (Body Mass Index) is a measure of body weight relative to height, used to assess if a person is underweight, normal weight, overweight, or obese. BMR (Basal Metabolic Rate) is the amount of energy your body needs to function at rest, without any physical activity. In summary, BMI is a measure of body weight, while BMR is a measure of energy expenditure.