BMR & TDEE Calculator
Estimate your basal metabolic rate and daily maintenance calories.
How it works
Enter your age, sex, weight and height, then pick the activity level that matches your usual week. The calculator works out BMR from the formula you choose, then multiplies it by the activity factor to give your estimated maintenance calories.
Mifflin-St Jeor (kg, cm, years):
male BMR = 10 × weight + 6.25 × height − 5 × age + 5
female BMR = 10 × weight + 6.25 × height − 5 × age − 161
TDEE = BMR × activity factor
(1.2, 1.375, 1.55, 1.725 or 1.9)Example
A 30-year-old man, 70 kg and 170 cm: BMR = 10 × 70 + 6.25 × 170 − 5 × 30 + 5 = 1,617.5, shown as 1,618 kcal/day. At moderate activity (× 1.55), TDEE = 1,617.5 × 1.55 = 2,507 kcal/day.
Common mistakes
- Picking an activity level that is too high. The factors already count exercise, so choose the one that matches an ordinary week.
- Treating the result as exact. It is an estimate from an equation, and real needs vary from person to person.
- Mixing up units. Check whether the weight and height are in kg and cm or lb and ft/in; the unit toggle converts for you.
Results are estimates and are not a substitute for medical advice.
About this calculator
BMR is an estimate of the energy your body uses at rest. TDEE multiplies it by an activity factor to estimate the calories you use in a typical day. This calculator uses the Mifflin-St Jeor equation by default, and offers the revised Harris-Benedict equation as an alternative.
Both equations are population averages, so your own figure can differ. It does not use body fat or lean mass, and it is meant for ages 15 to 100. Use the result as a starting point, not a measurement.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is the energy your body uses at rest. TDEE adds the energy you use moving around and exercising, so it is BMR multiplied by an activity factor.
Which formula does this use?
Mifflin-St Jeor by default: 10 × kg + 6.25 × cm − 5 × age, plus 5 for male or minus 161 for female. You can switch to the revised Harris-Benedict equation, which gives a somewhat different BMR for the same person.
Which activity level should I choose?
Choose the one that matches a typical week: sedentary (× 1.2) for little exercise, light (× 1.375) for 1–3 days, moderate (× 1.55) for 3–5 days, very active (× 1.725) for 6–7 days, and extra active (× 1.9) for very hard training or a physical job. The table under the result shows all five.
Why only ages 15 to 100?
The equations were developed for adults, and the calculator does not apply them outside that range. Outside it you will see a message instead of a number.