Find out how many calories your body burns at rest. This free BMR calculator uses the Mifflin-St Jeor equation and adds your activity level to estimate your daily maintenance calories (TDEE).
About you
yrs
cm
kg
ftin
lb
Your BMR
— cal/day
Enter your details
Maintenance (TDEE)
—
Per hour (at rest)
—
Activity factor
—
Equation
Mifflin-St Jeor
BMR is the energy your body uses at rest; TDEE adds your activity. These are estimates — for personal nutrition guidance, talk to a doctor or registered dietitian.
Use this free BMR calculator to estimate your Basal Metabolic Rate — the calories your body burns at rest. Enter your age, sex, height and weight to see your BMR and your daily maintenance calories (TDEE).
What this BMR calculator shows you
A BMR calculator estimates your Basal Metabolic Rate — the energy your body uses just to keep functioning at complete rest. Add your activity level and it also gives your TDEE (Total Daily Energy Expenditure), the calories you burn in a typical day including movement.
How BMR is calculated
Mifflin-St Jeor:
BMR = 10·weight(kg) + 6.25·height(cm) − 5·age + s
(s = +5 for men, −161 for women)
For a 30-year-old man, 175 cm and 70 kg, that’s about 1,649 calories a day at rest. The Mifflin-St Jeor equation is the modern standard used by most dietitians.
BMR vs TDEE
BMR is what you’d burn lying in bed all day. TDEE multiplies BMR by an activity factor to reflect real life — from ×1.2 for sedentary up to ×1.9 for very active. TDEE is the more useful figure for understanding daily energy needs.
Activity multipliers
Activity level
Multiplier
Sedentary (little exercise)
× 1.2
Light (1–3 days/week)
× 1.375
Moderate (3–5 days/week)
× 1.55
Active (6–7 days/week)
× 1.725
Very active (physical job/training)
× 1.9
How to use the BMR calculator
Select your sex and units.
Enter your age, height and weight.
Choose your activity level.
Read your result. Your BMR and TDEE appear instantly.
BMR terms glossary
Term
What it means
BMR
Calories burned at complete rest.
TDEE
Total daily calories including activity.
Mifflin-St Jeor
The current standard BMR equation.
Activity factor
A multiplier reflecting how active you are.
BMR Calculator FAQ
What is BMR?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to keep functioning breathing, circulation and basic cell activity. It's the largest part of most people's daily energy use.
How is BMR calculated?
This calculator uses the Mifflin-St Jeor equation: 10 × weight(kg) + 6.25 × height(cm) − 5 × age, then +5 for men or −161 for women. A 30-year-old man at 175 cm and 70 kg has a BMR of about 1,649 calories.
What's the difference between BMR and TDEE?
BMR is your at-rest calorie burn; TDEE (Total Daily Energy Expenditure) multiplies it by an activity factor to estimate everything you burn in a day, including movement and exercise.
Which activity level should I choose?
Pick the one that matches a typical week: sedentary for little exercise, moderate for 3–5 active days, very active for a physical job or daily training. It's an estimate, so choose honestly.
Should I use BMR to set calorie goals?
BMR and TDEE are useful reference points, but calorie goals are personal and depend on your health, body and aims. For a tailored plan, speak with a doctor or registered dietitian rather than relying on a formula alone.
Is the BMR calculator free to use?
Yes, this BMR calculator is completely free, needs no sign-up, and gives instant results directly in your browser.
