RMR Calculator
Resting metabolic rate is what you burn sitting quietly at rest. It is measured under less strict conditions than basal metabolic rate, so it runs slightly higher. These two equations were developed from RMR measurements in both normal-weight and obese adults.
Owen equation
kcal/day
Enter your age and weight
Livingston-Kohlstadt
kcal/day
Livingston & Kohlstadt 2005 · weight and age
Two different RMR equations, shown separately. Both were built from measurements in normal-weight and obese adults.
Your results are attached to the form below
These figures are estimates for general awareness only and are not medical advice or a diagnosis. Read our Medical Disclaimer.
Want a Plan Built Around Your Numbers?
A certified dietitian will turn these figures into a diet that fits your routine and your food.
How this is calculated
Owen equations (American Journal of Clinical Nutrition): women RMR = 795 + 7.18 × weight (1986; trained athletes 50.4 + 21.1 × weight); men RMR = 879 + 10.2 × weight (1987). Livingston & Kohlstadt (Obesity Research, 2005): women RMR = 248 × weight^0.4356 − 5.09 × age; men RMR = 293 × weight^0.4330 − 5.92 × age. Weight in kg.
RMR or BMR?
BMR has strict measurement conditions: awake but lying down, 10–12 hours after eating, after a night's rest, relaxed, in a room neither warm nor cool enough to make the body work (FAO/WHO/UNU). RMR is measured at rest under less strict conditions, which makes it easier to measure in practice. In everyday use the two are close and the terms are often used interchangeably.
Why these two equations
Owen's studies found that older equations overestimated the resting metabolism of both women and men, and that body weight alone predicted it well. Livingston and Kohlstadt fitted a power curve to weight, plus an age term, that gave reasonable estimates for both normal-weight and obese people. Neither needs your height.
Related calculators
For BMR use the Mifflin-St Jeor, Harris-Benedict or BEE calculators; for daily calories, the TDEE Calculator.
More Diet & Nutrition Calculators
See all →- Protein Calculator Find your daily protein requirement using ICMR-NIN 2020, with separate figures for exercise, age 65+, pregnancy and breastfeeding.
- Calorie Deficit Calculator See your maintenance calories and a daily calorie target for weight loss, with two BMR formulas side by side.
- Macro Calculator Split your daily calories into grams of protein, carbohydrate and fat — balanced, higher-protein or your own ratio.
- Calorie Calculator How many calories do you need a day? See three recognised methods side by side — the clinic's, the US standard and India's ICMR-NIN.
- TDEE Calculator Your total daily energy expenditure with four BMR equations compared, and a breakdown of how much goes on rest, digestion and activity.
- Maintenance Calorie Calculator The calories that keep your weight steady — today, and at your goal weight, so you know what to eat once you get there.