BMR and TDEE Calculator
Estimate how many calories your body uses at rest (BMR) and across a typical day including activity (TDEE), using a choice of established equations.
Result
Enter your values and select Calculate to see the result.
How to use this calculator
- Choose units and the sex used by the equation, then enter age, weight and height.
- Choose an equation. Mifflin-St Jeor is a common default. Katch-McArdle needs a body-fat percentage instead of sex and height.
- Choose the activity level that best describes a typical week.
Formula
Mifflin-St Jeor (1990)
- Men: BMR = 10 × kg + 6.25 × cm − 5 × age + 5
- Women: BMR = 10 × kg + 6.25 × cm − 5 × age − 161
Revised Harris-Benedict (Roza and Shizgal, 1984)
- Men: BMR = 88.362 + 13.397 × kg + 4.799 × cm − 5.677 × age
- Women: BMR = 447.593 + 9.247 × kg + 3.098 × cm − 4.330 × age
Katch-McArdle
- BMR = 370 + 21.6 × lean body mass (kg), where lean mass = weight × (1 − body fat %)
TDEE = BMR × activity multiplier (1.2, 1.375, 1.55, 1.725 or 1.9).
Worked example
Mifflin-St Jeor
A 35-year-old woman, 65 kg, 165 cm:
BMR = 650 + 1,031.25 − 175 − 161 = 1,345 kcal/day.
Moderately active (× 1.55): TDEE ≈ 2,085 kcal/day.
Assumptions and limitations
- These equations estimate average needs for groups of people. Individual results can differ by 10% or more because of genetics, body composition, health conditions and medication.
- The equations ask for sex because they were derived from male and female study groups; they do not account for every individual’s physiology.
- They were developed for adults and are less reliable for under-18s, during pregnancy or breastfeeding, and for some medical conditions.
- This is not medical or nutritional advice. Consult a qualified professional before making significant dietary changes.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is the energy your body uses at complete rest. TDEE adds the energy used for daily movement, exercise and digesting food.
Which equation should I use?
Mifflin-St Jeor is widely used and generally performs well for adults. Katch-McArdle can be more accurate if you know your body-fat percentage reliably.