BMR & TDEE Daily Energy Expenditure Calculator
Calculate Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using Mifflin-St Jeor and Katch-McArdle equations with activity multipliers.
Metabolic Profile
Caloric Targets by Goal
Activity Multiplier Schedule
About this tool
How to use it
- Select your preferred measurement units (US Imperial or Metric).
- Enter your biological sex, age, height, and current body weight.
- Optionally enter your body fat percentage to calculate energy expenditure with the Katch-McArdle lean body mass formula.
- Choose your physical activity multiplier and click Calculate BMR & TDEE to view maintenance calories and targeted deficit/surplus goals.
Why it matters
Total Daily Energy Expenditure (TDEE) establishes the fundamental thermodynamic baseline for weight management, athletic fueling, and body recomposition. Knowing your Basal Metabolic Rate (BMR) ensures caloric deficits remain above your resting physiological floor to preserve lean muscle and metabolic health.
When to use it
Use this calculator when establishing nutritional caloric goals for fat loss, muscle hypertrophy, reverse dieting, or adjusting energy intake as body weight changes.
Good to know
Metabolic calculations provide population-level mathematical estimates. True metabolic expenditure varies by up to 10% based on individual thyroid function, non-exercise activity thermogenesis (NEAT), and adaptive thermogenesis.
Common questions
What is the difference between BMR and TDEE?
Basal Metabolic Rate (BMR) is the baseline number of calories your body burns in 24 hours simply staying alive at complete rest (breathing, cellular repair, circulation, brain function). Total Daily Energy Expenditure (TDEE) is your BMR multiplied by your physical activity level plus the thermic effect of food and deliberate exercise.
Which BMR formula is the most accurate?
The Mifflin-St Jeor equation is considered the clinical standard for individuals with average body fat percentages. However, if your body fat percentage is measured accurately (via DEXA scan or hydrostatic weighing), the Katch-McArdle formula is often more precise because it calculates energy expenditure directly from Lean Body Mass (LBM).
Should you ever eat below your BMR?
Prolonged caloric intake significantly below your BMR can trigger metabolic adaptation, elevated cortisol, muscle tissue catabolism, and hormonal suppression. For safe and sustainable fat loss, standard clinical practice recommends setting a 250 to 500 calorie deficit below your TDEE, while keeping total intake near or above your BMR.
How often should I recalculate my TDEE?
Recalculate your TDEE every 10 to 15 lbs (4.5 to 7 kg) of weight loss or gain, or whenever your weekly training frequency or daily occupational activity significantly shifts.
What is NEAT and how does it affect TDEE?
Non-Exercise Activity Thermogenesis (NEAT) encompasses all energy expended for everything that is not sleeping, eating, or structured sports exercise (e.g. walking, typing, taking stairs, fidgeting). NEAT can account for a variance of 300 to 800+ calories per day between individuals with similar body weights.