Adult energy reference
Energy Expenditure Estimator
Estimate resting energy expenditure and an activity-adjusted daily range with the Mifflin-St Jeor equation. This is not a calorie prescription or nutrition plan.
Complete the adult equation inputs to see an energy expenditure estimate.
How energy expenditure is estimated
This tool estimates your Basal Metabolic Rate (BMR) — the calories your body burns at rest — using the Mifflin-St Jeor equation:
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(yr) + s
s = +5 for males, −161 for females
Your Total Daily Energy Expenditure (TDEE) is BMR multiplied by the activity range selected. Both the equation and the activity factor are approximations; this page does not translate the result into a diet or macro plan.
Activity multipliers
Activity multipliers are broad population assumptions, not measurements of an individual's movement or metabolism.
Related tools: Adult BMI Calculator · Weight Loss Calculator · All tools
Frequently asked questions
What is TDEE and how is it calculated?
TDEE (Total Daily Energy Expenditure) is the total calories you burn in a day. This tool first estimates your BMR with the Mifflin-St Jeor equation, then multiplies it by an activity factor (1.2 to 1.9) to account for movement and exercise. It's a general wellness estimate, not a measured value.
How accurate is the Mifflin-St Jeor equation?
Mifflin-St Jeor is a population equation, not a measurement. Individual results can differ because metabolism, body composition, health conditions, and the selected activity multiplier are not captured precisely.
Why does this estimator not provide calorie or macro targets?
A population equation cannot account for the full clinical, dietary, and metabolic context needed to prescribe an intake or macro split. A registered dietitian or qualified clinician can interpret energy needs for an individual goal.
Which activity level should I choose?
Choose the broad description that most closely resembles your usual movement. Activity multipliers are rough assumptions, so the result can vary substantially from measured energy expenditure.
Is this calculator medical or nutrition advice?
No. It's a general wellness estimate for educational purposes only and is not medical or nutrition advice, diagnosis, or treatment. Talk to your clinician or a registered dietitian before changing your diet, especially if you have a health condition.