RMR Calculator – How Many Calories Do You Burn at Rest?

What Is Resting Metabolic Rate (RMR)?

RMR is the number of calories your body burns at rest — when you’re not moving, eating, or digesting. It accounts for about 60–75% of your total daily energy expenditure (TDEE) and fuels essential processes like:

• Breathing and heart rate
• Brain and nerve function
• Body temperature regulation
• Digestion and hormone production

Unlike BMR (Basal Metabolic Rate), which is measured under strict clinical conditions, RMR reflects real-life metabolism more closely.

RMR vs. BMR: What’s the Difference?

That’s why most calculators, including ours, prioritize RMR.

How This RMR Calculator Works

This tool uses either the Harris-Benedict or Mifflin-St Jeor formula, depending on your selection. Input your age, weight, height, and gender. Optionally, we also include a 10% adjustment for the Thermic Effect of Food (TEF).

Harris-Benedict Formula

Men:    RMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) – (5.677 × age)
Women:  RMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) – (4.330 × age)

Mifflin-St Jeor Formula

Men:    RMR = (10 × weight) + (6.25 × height) – (5 × age) + 5
Women:  RMR = (10 × weight) + (6.25 × height) – (5 × age) – 161

Example RMR Calculation

Profile: Male, 30 years old, 75kg, 175cm

Harris-Benedict RMR: 88.362 + (13.397 × 75) + (4.799 × 175) – (5.677 × 30) = ~1,739 kcal/day

This is how many calories he’d burn at complete rest.

What Affects Your Resting Metabolic Rate?

• Age: Metabolism slows as you age
• Muscle Mass: More muscle = higher RMR
• Gender: Males typically have a higher RMR
• Genetics: Some people naturally burn more
• Diet History: Crash diets lower RMR
• Climate: Cold environments can raise RMR

How to Use Your RMR for Weight or Fitness Goals

Once you know your RMR, you can calculate your total daily energy needs (TDEE) by multiplying it by your activity level:

To lose weight: Eat slightly fewer calories than your TDEE.
To gain muscle: Eat a surplus above your TDEE.

Tips to Naturally Improve Your RMR

• Build lean muscle with resistance training
• Avoid extreme calorie deficits or crash diets
• Get 7–9 hours of sleep nightly
• Eat protein-rich meals to increase TEF
• Stay physically active throughout the day (NEAT)

Frequently Asked Questions (FAQs)

Reviewed by a Certified Expert

Reviewed by: Dr. Caleb Morrison, PhD, RDN – Metabolic Health Specialist

Disclaimer: This calculator is for informational purposes only. Please consult your physician or registered dietitian for personalized advice.

Start Optimizing Your Health Today

🎯 Curious how many calories your body burns at rest? Use our RMR Calculator now to get your personalized result and take the first step toward smarter weight management or muscle-building goals.