BMR Calculator

Calculate your Basal Metabolic Rate using the Mifflin-St Jeor equation. Find out exactly how many calories you burn resting.

Your Demographics

Male

Female

Age

Height cm

Weight kg

Basal Metabolic Rate (BMR)

Calories / day

This is the exact number of calories your body burns while at complete rest.

Daily Calorie Needs By Activity Level:

Sedentary

Little or no exercise

kcal/day

Lightly Active

Light exercise/sports 1-3 days/week

kcal/day

Moderately Active

Moderate exercise/sports 3-5 days/week

kcal/day

Very Active

Hard exercise/sports 6-7 days/week

kcal/day

Extra Active

Very hard exercise/physical job

kcal/day

Calculated using the highly accurate Mifflin-St Jeor Equation. To lose weight organically, consume fewer calories than your activity level dictates (Caloric Deficit).

How to use BMR Calculator

1
Select your gender and unit preference (Metric/Imperial).
2
Enter your age, height, and weight.
3
Review your exact BMR at the right side.
4
Scroll down to see total daily calorie estimates based on your activity level.

Frequently Asked Questions

What is BMR?

Basal Metabolic Rate is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions if you rested in bed all day.

Detailed Guide

What Is Your BMR?

Your Basal Metabolic Rate (BMR) is the number of calories your body burns just to stay alive — breathing, circulating blood, repairing cells, maintaining body temperature — while you're completely at rest.

Think of it this way: if you lay in bed all day without moving, your BMR is the minimum number of calories you'd need to consume to not lose weight. It doesn't account for walking to the bathroom, making coffee, or any other activity. Pure resting energy expenditure.

Your BMR is determined primarily by four factors: your sex, age, height, and weight. Muscle tissue burns more calories than fat tissue, which is why two people with identical height and weight can have meaningfully different BMRs depending on their body composition.

The Formulas — Which One Are We Using?

There are several equations for estimating BMR. We support the two most widely used:

Mifflin-St Jeor (Our Default)

Developed in 1990 and considered the most accurate for most people:

	Formula
Men	10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) + 5
Women	10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) − 161

Harris-Benedict (Revised 1984)

An older formula, revised from the original 1919 version. Still widely cited but slightly less accurate for modern populations with more sedentary lifestyles:

	Formula
Men	88.362 + (13.397 × weight) + (4.799 × height) − (5.677 × age)
Women	447.593 + (9.247 × weight) + (3.098 × height) − (4.330 × age)

Both formulas are estimates. Individual results can vary by 10–15% due to genetics, hormonal differences, and body composition that the equations can't capture.

From BMR to TDEE: Your Full Daily Calorie Needs

BMR is just the starting point. To find how many calories you actually need each day, you multiply your BMR by an activity multiplier to get your Total Daily Energy Expenditure (TDEE):

Activity Level	Description	Multiplier
Sedentary	Desk job, minimal exercise	BMR × 1.2
Lightly active	Light exercise 1–3 days/week	BMR × 1.375
Moderately active	Moderate exercise 3–5 days/week	BMR × 1.55
Very active	Hard exercise 6–7 days/week	BMR × 1.725
Extremely active	Physical job + heavy exercise daily	BMR × 1.9