BMR — Basal Metabolic Rate (Mifflin–St Jeor)
Estimate your basal metabolic rate (kcal/day) using the Mifflin–St Jeor equation.
Inputs
Required for the equation constant.
Enter full years.
Source-value unit switching keeps conversions clean.
Switching units preserves the original source value.
Results
Basal Metabolic Rate (BMR)
—
Mifflin–St Jeor estimate in kcal/day
Quick summary
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Step-by-step derivation
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Mifflin–St Jeor reference
Formula (kcal/day):
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(y) + s
with s = +5 (male),
s = −161 (female).
Sources
• Mifflin MD, St Jeor ST, et al. “A new predictive equation for resting energy expenditure in healthy individuals.” AJCN, 1990.
• General dietetics references for BMR vs. TDEE concepts.
• General dietetics references for BMR vs. TDEE concepts.
Use this BMR Calculator to estimate how many calories your body uses each day at rest. It uses the Mifflin–St Jeor equation with your age, sex, height, and weight.
Calculation Method
Male:
BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
Female:
BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
Example
For a 30-year-old woman weighing 65 kg and measuring 165 cm:
BMR = 10 × 65 + 6.25 × 165 − 5 × 30 − 161
BMR ≈ 1,370 kcal/day
This means her estimated resting energy requirement is about 1,370 calories per day.
Important Note
BMR represents estimated resting energy use. It does not include exercise, walking, work, digestion, or other daily activity. Actual metabolic rate can also differ from the equation estimate.