Home / Calculators / Basal Metabolic Rate Calculator
Basal Metabolic Rate Calculator
Basal metabolic rate (BMR) is the energy your body burns at complete rest: for breathing, heart and brain function, and maintaining body temperature. It is the starting point for calculating your daily calorie needs.
How it is calculated
Mifflin-St Jeor (1990): 10 × weight (kg) + 6.25 × height (cm) − 5 × age, + 5 for men or − 161 for women. Harris-Benedict (1984 revision): for men, 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age; for women, 447.593 + 9.247 × weight + 3.098 × height − 4.330 × age. The Mifflin-St Jeor formula is more accurate for modern lifestyles, so YaYo uses it by default.
Frequently Asked Questions
How does BMR differ from daily calorie needs?
Basal metabolic rate is what you burn at complete rest. Your daily calorie needs equal your BMR multiplied by an activity factor: from 1.2 for sedentary work up to 1.725 for daily workouts.
Can you eat below your BMR?
Staying below your BMR for an extended time is not recommended: it increases the risk of nutrient deficiencies and muscle loss. For weight loss, a moderate deficit from your total daily energy expenditure is enough.
Why does metabolism slow down with age?
Muscle mass typically decreases with age, and muscle burns more energy than fat. Strength training and eating enough protein help preserve muscle.
Formulas provide an estimate: your actual metabolic rate may vary by 10% or more.
YaYo will track this target every day
Snap a photo of your food — YaYo will automatically calculate calories and macros, showing how much you have left for today.