What is Resting Metabolic Rate (RMR)?

RMR is the number of calories your body burns at rest to perform vital life-sustaining processes (breathing, heartbeats, cellular repair).

How is RMR calculated?

The calculator uses the Revised Harris-Benedict equation, which factors in sex, age, height, and weight to project resting energy demands.

How does RMR differ from BMR?

BMR requires strict fasting and overnight rest in a laboratory. RMR is measured under less restrictive conditions and is typically 5-10% higher.

Can I increase my RMR?

Yes. Building lean muscle mass through resistance training is the most effective way to permanently raise RMR, as muscle is more metabolically active than fat.

What is the Revised Harris-Benedict equation for men?

RMR = 88.362 + 13.397 × Weight (kg) + 4.799 × Height (cm) - 5.677 × Age (years).

What is the Revised Harris-Benedict equation for women?

RMR = 447.593 + 9.247 × Weight (kg) + 3.098 × Height (cm) - 4.330 × Age (years).

How does age affect my resting metabolism?

RMR naturally declines with age, primarily because muscle mass decreases (sarcopenia). Strength training preserves muscle and metabolic rates.

Does weight loss lower my RMR?

Yes. A smaller body requires fewer calories to maintain. Additionally, prolonged deficits can trigger metabolic adaptation, lowering RMR.

Is RMR the same as maintenance calories?

No. RMR is what you burn at rest. To find maintenance calories (TDEE), multiply your RMR by an activity factor representing your daily movement.

Why is RMR higher in men?

Men typically possess higher skeletal muscle mass and lower essential body fat percentages than women of similar weight, raising resting energy needs.

health calculator

Resting Metabolic Rate Calculator

Calculate calories burned daily at complete rest using metabolic models.

Formula Verified by Dr. Sarah Jenkins, PhD

Quick actions: Save inputs, view saved runs, print, share, or export results

Saved Runs

Inputs

Gender

Weight (kg)kg

Height (cm)cm

Age (years)years

Body fat % (optional)%

Results

Resting Metabolic Rate

1649 kcal/day

Mifflin-St Jeor Estimate1649 kcal/day

Formula

RMR formulas

Mifflin: 10w + 6.25h - 5a + s (s = +5 for male, -161 for female). Katch-McArdle: 370 + 21.6 × LBM(kg)

Mifflin uses total weight. Katch-McArdle uses Lean Body Mass (LBM) for athletic individuals.

Step by step

How the calculation works

1Enter weight in kilograms, height in centimeters, and age in years.
2Choose your physiological gender.
3Provide body fat percentage (optional) to compute the Katch-McArdle formula, which is more accurate for individuals with higher muscle mass.

Related guides

Learn more about this calculation

Guide

RMR Calculation Guide: Mifflin and Katch-McArdle

Estimate resting metabolic rate with the exact DTC formulas, compare Mifflin-St Jeor with Katch-McArdle, and understand the limits.

Site Guide

How to Use Do The Calculation Calculators: A Practical Step-by-Step Guide

Learn the fastest reliable workflow for using Do The Calculation calculators, reading results, checking formulas, and using save, print, share, and export actions correctly.

health calculator

Resting Metabolic Rate Calculator

Calculate calories burned daily at complete rest using metabolic models.

Formula Verified by Dr. Sarah Jenkins, PhD

Quick actions: Save inputs, view saved runs, print, share, or export results

Saved Runs

Inputs

Gender

Weight (kg)kg

Height (cm)cm

Age (years)years

Body fat % (optional)%

Results

Resting Metabolic Rate

1649 kcal/day

Mifflin-St Jeor Estimate1649 kcal/day

Summary

Key output metrics

Resting Metabolic Rate

1649 kcal

Calories burned at complete rest.

Mifflin-St Jeor

1649 kcal

Standard weight-based formula.

Katch-McArdle

N/A

Lean body mass formula.

D3 visualization

Metabolic rate formula comparison

Compare the caloric burn estimate between the weight-based Mifflin-St Jeor formula and the lean-mass-based Katch-McArdle formula (if body fat is provided).

Formula

RMR formulas

Mifflin: 10w + 6.25h - 5a + s (s = +5 for male, -161 for female). Katch-McArdle: 370 + 21.6 × LBM(kg)

Mifflin uses total weight. Katch-McArdle uses Lean Body Mass (LBM) for athletic individuals.

Step by step

How the calculation works

1Enter weight in kilograms, height in centimeters, and age in years.
2Choose your physiological gender.
3Provide body fat percentage (optional) to compute the Katch-McArdle formula, which is more accurate for individuals with higher muscle mass.

Related guides

Learn more about this calculation

Guide

RMR Calculation Guide: Mifflin and Katch-McArdle

Estimate resting metabolic rate with the exact DTC formulas, compare Mifflin-St Jeor with Katch-McArdle, and understand the limits.

Site Guide

How to Use Do The Calculation Calculators: A Practical Step-by-Step Guide

Learn the fastest reliable workflow for using Do The Calculation calculators, reading results, checking formulas, and using save, print, share, and export actions correctly.