Resting Metabolic Rate (RMR) Calculator
Calculate the calories your body burns at rest using the Mifflin-St Jeor Equation.
Your Estimated Resting Metabolic Rate:
0Calories per day
This is the energy required to maintain basic physiological functions while at rest.
What is Resting Metabolic Rate (RMR)?
Resting Metabolic Rate (RMR) represents the total number of calories your body burns while at complete rest. This includes vital functions such as breathing, circulating blood, organ function, and basic neurological processes. Unlike Basal Metabolic Rate (BMR), which is measured under strict laboratory conditions, RMR is a more practical estimate of your daily energy expenditure in a relaxed, non-active state.
How is RMR Calculated?
This calculator uses the Mifflin-St Jeor Equation, which is currently considered the most accurate standard for predicting metabolic rate in healthy adults. The formulas are as follows:
- For Men: RMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
- For Women: RMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Factors That Influence Your RMR
| Factor | Impact on RMR |
|---|---|
| Muscle Mass | Higher muscle mass increases RMR because muscle tissue is more metabolically active than fat. |
| Age | RMR typically decreases with age due to loss of lean muscle mass and hormonal changes. |
| Body Size | Larger bodies (both taller and heavier) generally have higher RMRs because there is more tissue to maintain. |
| Genetics | Some individuals naturally have a "faster" or "slower" metabolism based on hereditary factors. |
Why Knowing Your RMR Matters
Understanding your RMR is the cornerstone of any weight management plan. Once you know your RMR, you can apply an "activity factor" to determine your Total Daily Energy Expenditure (TDEE). If you consume more calories than your TDEE, you will gain weight; if you consume fewer, you will lose weight.
Example Calculation
A 35-year-old male weighing 80kg (176 lbs) and standing 180cm (5'11") tall:
Calculation: (10 × 80) + (6.25 × 180) – (5 × 35) + 5 = 800 + 1125 – 175 + 5 = 1,755 calories/day.