TDEE Calculator
Your TDEE (Total Daily Energy Expenditure) is the number of calories your body burns in a full day — including everything from breathing and sleeping to workouts and fidgeting. Eat below it and you lose weight; eat above it and you gain. This calculator estimates your TDEE with the Mifflin-St Jeor equation, the most validated formula for healthy adults.
Estimates only — real expenditure varies ±10–15% person to person. Track your weight for 2–3 weeks and adjust.
How to use this TDEE calculator
- Enter your sex, age, height, and weight.
- Pick the activity level that honestly matches your week — most people overestimate this, so when in doubt choose one level lower.
- Read your TDEE, then use the fat-loss (~15% deficit) or muscle-gain (~10% surplus) targets as starting points.
The formula: Mifflin-St Jeor
This calculator uses the Mifflin-St Jeor equation to estimate basal metabolic rate (BMR), then multiplies by an activity factor:
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
TDEE = BMR × activity factor (1.2–1.9)
Published in 1990 and validated against indirect calorimetry, it remains the most accurate widely-used prediction equation for healthy adults.
Understanding your results
BMR is what you would burn lying in bed all day. TDEE adds movement and exercise. For fat loss, a 15–20% deficit typically yields 0.5–1 lb per week; for lean muscle gain, a 5–10% surplus keeps fat gain minimal. Re-check every few weeks as your weight changes.
Frequently asked questions
What is TDEE?
TDEE stands for Total Daily Energy Expenditure — the total calories your body burns in 24 hours, including your basal metabolic rate, daily movement, exercise, and the energy cost of digesting food.
How accurate is a TDEE calculator?
Prediction equations like Mifflin-St Jeor are typically accurate within ±10–15% for most people. Treat the number as a starting point, then adjust based on how your weight actually responds over 2–3 weeks.
Should I eat back exercise calories?
No — your activity level selection already accounts for exercise. Adding exercise calories on top usually double-counts them and stalls fat loss.
Why is my TDEE lower than I expected?
Most people overestimate their activity level. A desk job with 3–4 gym sessions per week is “moderately active,” not “very active.” Try one level lower and see how your weight responds.
How often should I recalculate my TDEE?
Every 5–10 lbs of weight change, or every 4–6 weeks during a cut or bulk, since a lighter or heavier body burns a different number of calories.