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BMR Calculator

Find out how many calories your body burns at complete rest. Compare Mifflin-St Jeor and Harris-Benedict BMR formulas and see your TDEE for every activity level.

Quick Calculator Get a fast estimate
yrs
kg
cm
BMR — Mifflin-St Jeor
1 618 kcal/day
BMR — Harris-Benedict
1 672 kcal/day
Average BMR
1 645 kcal/day
TDEE — Sedentary (×1.2)
1 941 kcal/day
TDEE — Light Activity (×1.375)
2 224 kcal/day
TDEE — Moderate Activity (×1.55)
2 507 kcal/day
TDEE — Very Active (×1.725)
2 790 kcal/day
TDEE — Extra Active (×1.9)
3 073 kcal/day
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How to Use the BMR Calculator

Select your gender, then enter your age, weight in kilograms, and height in centimetres. The calculator computes your Basal Metabolic Rate (BMR) using two established equations and shows your Total Daily Energy Expenditure (TDEE) across all five activity levels.

The Extended Calculator below compares four BMR formulas side by side and shows a TDEE bar chart for every activity level. The Professional Calculator adds Katch-McArdle lean mass adjustment, metabolic age estimation, and macro targets per activity level.

Need more detail?
📊 Extended Calculator More options, charts, and scenario comparison
kg
cm
years
BMR (Mifflin-St Jeor)
1699 kcal/day
TDEE (moderate)
2633 kcal
TDEE (active)
2930 kcal
TDEE by Activity Level
2039Sedentary2336Light2633Moderate2930Active3228Extreme050010001500200025003000
BMR Formula Comparison
FormulaBMRTDEE (mod)
Mifflin-St Jeor (1990)16992633
Harris-Benedict (1919)17632732
Schofield (1985)13962164
Katch-McArdle (lean)16662582
Average (3 formulas)16192510

BMR Formulas

Mifflin-St Jeor (Male): (10 × kg) + (6.25 × cm) − (5 × age) + 5

Mifflin-St Jeor (Female): (10 × kg) + (6.25 × cm) − (5 × age) − 161

Harris-Benedict (Male): 88.362 + (13.397 × kg) + (4.799 × cm) − (5.677 × age)

Harris-Benedict (Female): 447.593 + (9.247 × kg) + (3.098 × cm) − (4.33 × age)

TDEE: BMR × Activity Multiplier

Example

Female, 28 years old, 62 kg, 165 cm:

Mifflin BMR = (10 × 62) + (6.25 × 165) − (5 × 28) − 161 = 1,370 kcal/day

Moderate TDEE (×1.55) = 1,370 × 1.55 = 2,124 kcal/day

Need full precision?
🔬 Professional Calculator Complete parameters, sensitivity analysis, and detailed breakdown
kg
cm
years
%
Katch-McArdle BMR (body-comp adjusted)
1752 kcal/day
Mifflin-St Jeor BMR
1738 kcal
Lean Body Mass
64.0 kg
TDEE (current activity)
2715 kcal
Metabolic Age
~50 years
Macros per Activity Level
ActivityTarget kcalProteinCarbsFat
Sedentary2102128g266g58g
Lightly Active2408128g324g67g
Moderately Active2715128g381g75g
Very Active3021128g439g84g
Extremely Active3328128g496g92g
About Metabolic Age

Metabolic age compares your BMR to the average BMR for your actual age group. A metabolic age lower than your chronological age suggests a higher-than-average metabolic rate — often associated with more lean muscle mass.

Your estimated metabolic age: ~50 years

This is an estimate based on population averages. It is not a clinical measurement.

Frequently Asked Questions

BMR (Basal Metabolic Rate) is the number of calories your body needs to sustain basic life functions — breathing, circulation, and cell production — at complete rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor to account for movement throughout the day.
Multiple studies show that the Mifflin-St Jeor equation (1990) is slightly more accurate for most modern adults. The Harris-Benedict equation (revised 1984) is also well-validated. Using the average of both gives a robust estimate.
Eating at BMR level (below TDEE) will cause weight loss, but consistently eating only your BMR calories can slow metabolism, cause nutrient deficiencies, and lead to muscle loss. Most guidelines recommend not going below 1,200 kcal/day for women and 1,500 kcal/day for men without medical supervision.
Yes. BMR generally decreases with age, primarily because muscle mass tends to decrease over time. Regular strength training can help slow this decline by preserving metabolically active muscle tissue.

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