RMR Calculator - Resting Metabolic Rate

This calculator uses scientifically validated predictive equations—specifically modified versions of the Harris-Benedict formulas—to estimate your daily energy expenditure at rest, multiplied by a standard 1.1 thermic effect factor. For males, the equation is RMR = ((13.75 × weight in kg) + (5 × height in cm) - (6.76 × age in years) + 66) × 1.1. For females, the equation is RMR = ((9.56 × weight in kg) + (1.85 × height in cm) - (4.68 × age in years) + 655) × 1.1. These formulas account for how lean mass, stature, and age naturally influence your baseline caloric burn.

Let us calculate the resting metabolic rate for a 35-year-old male who is 180 cm tall and weighs 80 kg. First, we plug the values into the male formula: (13.75 × 80) + (5 × 180) - (6.76 × 35) + 66. This breaks down to 1100 + 900 - 236.6 + 66, which equals 1829.4 calories. Finally, we multiply this base figure by 1.1 to incorporate the minor thermic adjustments, resulting in an RMR of approximately 2,012 calories per day.

Remember that RMR represents only the calories burned at rest; your Total Daily Energy Expenditure (TDEE) will be higher once physical activity and digestion are factored in. To protect your metabolic rate during weight loss, combine a modest caloric deficit with adequate protein intake and resistance training to preserve lean muscle tissue. Recalculate your RMR every few months or after significant weight changes to ensure your nutrition targets remain accurate.