BMR Calculator

Estimate the calories your body uses at rest with three established BMR equations, then view daily calorie estimates for different activity levels.

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Your estimate

Mifflin–St Jeor BMR1,608calories/day at complete rest
Estimated maintenance2,492 kcal/day
Harris–Benedict1,643 kcal/day
Katch–McArdleAdd body fat %
Weekly maintenance17,444 kcal
Use this as a starting point: Real energy needs vary. Track weight trends, appetite, training, sleep, and health advice before adjusting intake.

Daily calorie estimates by activity

ActivityMultiplierEstimated calories/day

How the estimate works

The main result uses the Mifflin–St Jeor equation. We also show the revised Harris–Benedict estimate for comparison. If body-fat percentage is supplied, the Katch–McArdle equation estimates resting needs from lean body mass.

Male: 10 × kg + 6.25 × cm − 5 × age + 5
Female: 10 × kg + 6.25 × cm − 5 × age − 161

BMR is not the same as daily calorie need. Total daily energy expenditure (TDEE) multiplies BMR by an activity factor and remains an estimate.

Frequently asked questions

What is BMR?

Basal metabolic rate is an estimate of the energy required for basic functions such as breathing, circulation, and temperature regulation at rest.

Which BMR equation is best?

Mifflin–St Jeor is widely used for adults, but no equation is exact for everyone. Comparing formulas and observing real trends provides useful context.

Can I use BMR alone for weight planning?

No. BMR excludes normal movement, exercise, and digestion. Use an estimated TDEE as a starting point and consult a qualified professional for individualized guidance.

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Health disclaimer: Results are educational estimates, not medical advice or a prescription. People who are pregnant, under 18, managing a medical condition, or concerned about nutrition should seek qualified professional advice.