🔥TDEE Calculator 2026 — Calculate Total Daily Energy Expenditure, BMR & Calorie Needs

Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day from all sources combined: keeping you alive at rest, digesting food, moving around, and structured exercise. The calculation is a two-step process: first compute Basal Metabolic Rate (BMR), the energy needed to keep core organs running while completely at rest, then multiply BMR by an activity factor that captures everything you do on top of that. The result is a single number — calories per day — that represents the energy your body actually expends, and therefore the energy intake at which your weight stays stable.

The most accurate BMR formula for the modern general population is the Mifflin-St Jeor equation (Mifflin et al., 1990), which is the default used by the American College of Sports Medicine and most clinical nutrition references. For men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5. For women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161. Mifflin-St Jeor was validated against indirect calorimetry on contemporary body compositions and is roughly 5% more accurate than the older Harris-Benedict equation (1919, revised 1984), which tends to overestimate BMR for sedentary modern adults. A third option, Katch-McArdle, is more accurate when you know your lean body mass and is preferred for athletes and very lean people: BMR = 370 + 21.6 × lean body mass (kg).

Once BMR is in hand, TDEE is BMR multiplied by an activity multiplier. The standard scale is: 1.2 for sedentary (desk job, little or no exercise), 1.375 for lightly active (light exercise 1–3 days per week), 1.55 for moderately active (moderate exercise 3–5 days per week), 1.725 for very active (hard exercise 6–7 days per week), and 1.9 for extra active (very hard daily exercise or a physically demanding job). The multipliers are pragmatic averages — actual non-exercise activity thermogenesis (NEAT) varies enormously between individuals. The single most common mistake people make with TDEE calculators is overestimating their activity level: a desk worker who trains three times a week is moderately active (1.55), not very active. Err lower if you are uncertain.

Goal-based caloric targets are derived from TDEE by adding or subtracting a deficit. Because one kilogram of body fat stores roughly 7,700 kcal, a deficit of 500 kcal per day produces approximately 0.5 kg per week of fat loss (3,500 kcal weekly deficit) — a sustainable rate that preserves lean mass. A 1,000 kcal/day deficit drives faster loss but raises the risk of muscle loss, hormonal disruption, and adherence breakdown. For weight gain, a 250–500 kcal/day surplus over TDEE produces a slow, mostly-lean bulk; larger surpluses simply add fat. Recalculate TDEE every 3–5 kg of body weight change because the formulas are weight-sensitive, and account for metabolic adaptation in extended cuts: TDEE may drop 10–15% during prolonged deficits, so plan diet breaks at maintenance every 8–12 weeks.

Macronutrient distribution converts the calorie target into grams of protein, fat and carbohydrates. Current evidence-based ranges from the Academy of Nutrition and Dietetics, ACSM, and the International Society of Sports Nutrition place protein at 1.6–2.2 g per kilogram of total body weight (or up to 2.4 g/kg in a calorie deficit to preserve lean mass), fat at 0.6–1.0 g per kilogram (with a floor of about 20% of calories to support hormone production), and carbohydrates filling the remaining calories — typically 3–7 g/kg depending on training volume. Each gram of protein and carbohydrate yields 4 kcal, each gram of fat yields 9 kcal, and each gram of alcohol yields 7 kcal; the calculator above uses these factors and a balanced 2 g/kg protein / 0.8 g/kg fat / rest carbs split as a sensible default.

TDEE is a model, not a measurement, so expect it to be within roughly ±10% of your true expenditure for most people in the BMI 18–40 range. The Pontzer et al. 2021 Science paper, the largest-ever doubly-labelled-water study, showed that adult TDEE is remarkably stable from age 20 to 60 and only declines about 0.7% per year after that — most of the perceived metabolic slowdown with age is actually loss of muscle mass, which resistance training largely offsets. If your weight is not moving in the direction your TDEE-based plan predicts after two consistent weeks, the most likely cause is under-reporting of food intake (people typically under-record by 15–25%) or over-reporting of activity. Use the calculator as a starting point, then adjust calories up or down by 100–200 kcal increments based on what the scale and the mirror actually show over 2–4 week windows. Source rates and the Mifflin-St Jeor equation come from the citations below.

• Mifflin-St Jeor (1990) – A new predictive equation for resting energy expenditure
• ACSM – Physical Activity Guidelines
• Academy of Nutrition and Dietetics – Energy and macronutrient recommendations
• EFSA – Dietary Reference Values for energy
• USDA – Dietary Guidelines for Americans 2020-2025