TDEE Calculator
Your TDEE — Total Daily Energy Expenditure — is the total number of calories your body burns in a day, from breathing and digestion to workouts and walking to the car. It is the single most useful number in nutrition: eat below it and you lose weight, eat at it and your weight stays stable, eat above it and you gain.
This free TDEE calculator estimates your daily calorie burn using the Mifflin-St Jeor equation, the formula the Academy of Nutrition and Dietetics found most accurate for healthy adults. Enter your sex, age, height and weight (US or metric units), pick the activity level that honestly matches your week, and you’ll instantly get your BMR, your TDEE, and three practical calorie targets: a 500-calorie deficit for fat loss (about one pound per week), your maintenance level, and a 300-calorie surplus for lean muscle gain. A BMI reference check is included. Because every body is a little different, treat the result as a starting point: eat at your target for two to three weeks, watch the trend on the scale, then adjust by 100–200 calories if needed.
Estimates use the Mifflin-St Jeor equation. Track your weight for 2–3 weeks and adjust ±100–200 kcal if the trend doesn’t match your goal.
How to Use This TDEE Calculator
- Choose Male or Female and enter your age.
- Enter your height and weight — switch between US (ft/in, lb) and metric (cm, kg) with the unit toggle; your numbers convert automatically.
- Pick the activity level that matches your typical week. Be honest: most desk workers are Sedentary or Light, even with occasional gym sessions.
- Results update instantly as you type — no button needed. Use the Weight Loss, Maintenance or Muscle Gain target that fits your goal.
The Formula: Mifflin-St Jeor Equation
This calculator first estimates your Basal Metabolic Rate (BMR) — the calories you’d burn at complete rest — then scales it by your activity level:
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
TDEE = BMR × activity factor
| Activity Level | Factor | Typical Lifestyle |
|---|---|---|
| Sedentary | ×1.2 | Desk job, little or no exercise |
| Light | ×1.375 | Exercise 1–3 days/week |
| Moderate | ×1.55 | Exercise 3–5 days/week |
| Very Active | ×1.725 | Exercise 6–7 days/week |
| Extra Active | ×1.9 | Physical job plus daily training |
Goal targets: Weight Loss subtracts 500 kcal/day (≈1 lb per week, since a pound of body fat stores roughly 3,500 kcal). Muscle Gain adds 300 kcal/day for a lean surplus of about 0.5 lb per week. The BMI reference divides weight(kg) by height(m)² — it’s a population screening measure and doesn’t account for muscle mass or body composition.
Source: Mifflin MD, St Jeor ST, et al. “A new predictive equation for resting energy expenditure in healthy individuals.” American Journal of Clinical Nutrition, 1990;51(2):241–247. A 2005 Academy of Nutrition and Dietetics systematic review found Mifflin-St Jeor the most reliable predictive equation for healthy adults — expect estimates within about ±10% for most people.
FAQ
What is TDEE?
TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a day, combining your basal metabolic rate (BMR) with all daily movement and exercise. Eating at your TDEE keeps your weight stable; eating below it drives fat loss; eating above it supports weight and muscle gain.
How accurate is the Mifflin-St Jeor equation?
A 2005 systematic review by the Academy of Nutrition and Dietetics found Mifflin-St Jeor the most accurate predictive equation for healthy adults, typically landing within about 10% of measured metabolic rate. Treat the result as a starting point: track your weight for 2–3 weeks and adjust by 100–200 kcal if needed.
How many calories should I eat to lose weight?
A deficit of 500 kcal per day below your TDEE loses roughly one pound per week, since a pound of body fat stores about 3,500 kcal. Most adults shouldn’t eat below 1,200 kcal (women) or 1,500 kcal (men) per day without medical supervision.
Which activity level should I choose?
Be conservative — most people overestimate. If you work a desk job and exercise a few times a week, Light or Moderate is usually right; if you sit all day with no formal exercise, choose Sedentary. Picking one level too high is the most common reason calorie targets fail.
Should I eat back the calories my watch says I burned?
Not on top of a multiplier that already includes exercise — that double-counts them. The activity factor in your TDEE already averages in your training. If you chose Sedentary but do occasional hard workouts, keep the deficit modest rather than adding back tracker estimates, which often overstate burn by 20% or more.
How often should I recalculate my TDEE?
Recalculate after every 10–15 lb of weight change, or whenever your activity level meaningfully changes. As you lose weight your TDEE drops, so a calorie target that worked at first can become maintenance later.