Calories Burned at Rest (BMR)
Calculate resting calorie burn
🔒 Browser-side · Method · · Disclaimer · Calories Burned at Rest (BMR)
Calories Burned at Rest (BMR) helps you calculate resting calorie burn — free, instant, in your browser. Fill in Weight (kg), Height (cm) and Age on Calories Burned at Rest (BMR) and read your answer immediately. Calories Burned at Rest (BMR) prints the result and its working. Calories Burned at Rest (BMR) suits budgeting and planning checks. Nothing is uploaded while Calories Burned at Rest (BMR) works, and the figures stay put. Calories Burned at Rest (BMR) is part of the Fitness & Exercise collection on CalcProMaster, alongside free online calories burned at rest (bmr) calculator, free calculators and more. Calories Burned at Rest (BMR) shows formula, assumptions and result together. Start with Calories Burned at Rest (BMR); the first number takes seconds.
What the defaults give
A 70 kg, 170 cm, 30-year-old man burns 1,618 cal a day at rest.
That is 67.4 calories an hour, before any movement at all.
The formula
Men: BMR = 10w + 6.25h − 5a + 5
Women: BMR = 10w + 6.25h − 5a − 161
Per hour = BMR ÷ 24
Weight in kilograms, height in centimetres, age in years. This is Mifflin-St Jeor, the equation most dietitians default to because it lands within about 10% of measured resting expenditure for most adults.
Worked examples
Male 70 kg / 170 cm / 30 → 1,618 cal/day, 67.4/hr
Female 60 kg / 165 cm / 30 → 1,320 cal/day, 55.0/hr
Male 80 kg / 180 cm / 30 → 1,804 cal/day, 75.2/hr
Female 50 kg / 160 cm / 25 → 1,214 cal/day, 50.6/hr
Male 70 kg / 170 cm / 50 → 1,518 cal/day, 63.3/hr
Female 70 kg / 170 cm / 30 → 1,463 cal/day, 61.0/hr
Resting burn is most of your day
For a sedentary adult, BMR is roughly 60% to 70% of total daily expenditure. Organs, brain and heart account for most of it: the liver and brain together use several hundred calories a day before any muscle moves. That is why cutting calories below BMR for long periods is both hard to sustain and counterproductive — the body reduces spontaneous movement and hormonal output to protect itself.
Adding activity changes the total but not the resting floor. A 1,618 BMR becomes about 1,940 at a sedentary multiplier of 1.2, 2,500 at moderate activity and over 3,000 with hard daily training. Exercise adds to the resting burn rather than replacing any of it.
Why the number will not match a smartwatch
Wearables estimate resting burn from heart rate and a proprietary formula, and they routinely differ from a predictive equation by 10% to 20%. Neither is a measurement: only indirect calorimetry, with a mask and a metabolic cart, measures it directly. The equation is a population average that happens to be a good starting point for an individual.
Body composition is the largest error source. Muscle is metabolically active, so two people at 70 kg with very different body fat have different resting burns, and this equation cannot see the difference — it uses total weight. If you know your lean mass, use a lean-mass equation instead. And treat the output as a baseline to calibrate: two weeks of consistent intake and daily weigh-ins will tell you more about your own maintenance level than any formula.
Frequently Asked Questions
How many calories does a 70 kg man burn at rest?
About 1,618 a day, or 67 an hour, by Mifflin-St Jeor with the standard male constant of +5.
Why are women 161 calories lower?
The female equation subtracts 161 instead of adding 5, reflecting the average difference in body composition at the same height and weight.
Is resting burn the same as daily calories?
No. It is the floor, before any activity. Multiply by 1.2 to 1.9 depending on how active you are to reach daily expenditure.
Why does my watch show a different number?
Wearables use heart rate and proprietary formulas and typically differ by 10–20%. Only indirect calorimetry measures resting expenditure directly.
Does muscle increase resting burn?
Yes, which is why body composition matters. This equation uses total weight and cannot separate muscle from fat, so a leaner person at the same weight burns more.
Bodyweight Strength Ratio and other Fitness tools
Bodyweight Strength Ratio · Beep Test VO₂ Max Estimator · VO2 Max Estimator · Training Max Calculator · Overhead Press Standards · Cycling Speed & Time · Fitness Guides