TDEE Calculator — Total Daily Energy Expenditure

The TDEE Calculator (Total Daily Energy Expenditure) estimates the total number of calories your body burns in a day — accounting for your basal metabolic rate, physical activity, and the energy cost of digestion. TDEE is the single most important number in nutrition and body composition: it is the calorie intake at which your weight stays perfectly stable. Eat below it to lose weight, above it to gain.

TDEE is the sum of four components. BMR (Basal Metabolic Rate) accounts for 60–75% — the calories needed to sustain vital functions at rest. EAT (Exercise Activity Thermogenesis) accounts for 15–30% — calories burned during planned workouts. NEAT (Non-Exercise Activity Thermogenesis) accounts for 5–15% — calories from daily movement like walking, typing, and standing. TEF (Thermic Effect of Food) accounts for 8–10% — the energy cost of digesting and metabolizing food. This calculator uses the Mifflin-St Jeor equation for BMR, then multiplies by an activity factor that estimates the combined EAT and NEAT contribution.

This calculator is recommended by the Academy of Nutrition and Dietetics and used in clinical nutrition settings worldwide. It provides the foundation for all calorie-based nutrition strategies — whether your goal is fat loss, muscle gain, athletic performance, or simply understanding how your body uses energy.

Example 1 — Sedentary office worker, female, 32 years, 68 kg, 165 cm: BMR = (10×68) + (6.25×165) − (5×32) − 161 = 680 + 1031 − 160 − 161 = 1,390 kcal TDEE = 1,390 × 1.20 = 1,668 kcal/day (maintenance) Weight loss target: ~1,168 kcal/day | Weight gain: ~1,968 kcal/day

Example 2 — Active male, 28 years, 82 kg, 180 cm, trains 5 days/week: BMR = (10×82) + (6.25×180) − (5×28) + 5 = 820 + 1125 − 140 + 5 = 1,810 kcal TDEE = 1,810 × 1.55 = 2,806 kcal/day (maintenance) Weight loss target: ~2,306 kcal/day | Lean bulk: ~3,106 kcal/day

Example 3 — Why generic '2,000 calories' is wrong: The USDA 2,000 kcal reference is a population average for label purposes — not a prescription. A 55 kg sedentary woman may need 1,400 kcal, while a 95 kg active man may need 3,200 kcal. Using a generic target instead of your personal TDEE is why most calorie-based diet plans fail.

Most popular diets fail because they prescribe arbitrary calorie targets — '1,200 calories for women' or '1,800 for men' — that have no relationship to individual metabolic needs. For a 90 kg active man, 1,800 kcal is a severe starvation-level deficit. For a 50 kg sedentary woman, 1,200 kcal may be close to her TDEE. Without knowing your TDEE, you cannot create a rational, sustainable nutrition plan.

Clinical research consistently shows that severe calorie restriction — eating far below TDEE — triggers adaptive thermogenesis: the body reduces its metabolic rate by 10–25% as a survival response. This metabolic adaptation is the primary biological reason crash diets fail. You lose weight rapidly at first, then stall as your body downregulates metabolism, and regain the weight when normal eating resumes — often with additional fat as the body overshoots in preparing for the next famine. Understanding your TDEE allows you to create a controlled, sustainable deficit that minimizes metabolic adaptation while preserving muscle mass.

TDEE is also the foundation of athletic performance nutrition. Endurance athletes may have TDEEs of 3,500–5,000 kcal/day during training blocks. Strength athletes may need 3,000–4,000 kcal to support muscle growth. Without knowing TDEE, neither fat loss nor muscle gain can be optimized — you are guessing at the most fundamental variable in nutrition science.

TDEE equations have a mean prediction error of 10–15% compared to doubly-labeled water measurements (the scientific gold standard for measuring actual energy expenditure). For a person with a calculated TDEE of 2,400 kcal, the actual value could range from 2,040 to 2,760 kcal. This is a significant range, which is why treating the calculated TDEE as a starting estimate — rather than a fixed fact — and adjusting based on real-world weight changes is critical.

The activity multipliers are the largest source of error. 'Moderately active' means different things to different people. Two individuals who both select 1.55 might have actual activity levels corresponding to 1.4 and 1.7. NEAT variation between individuals is enormous — up to 2,000 kcal/day difference — and is nearly impossible to estimate accurately without wearable tracking technology. For most accurate results, track food intake and body weight for 2–3 weeks, then calculate your actual TDEE from that real-world data.

The calculator also does not account for metabolic adaptation from prolonged calorie restriction, which can reduce actual TDEE by 10–30% in individuals who have been dieting for extended periods. If you have been in a calorie deficit for 3+ months and weight loss has stalled, your actual TDEE at that time may be substantially lower than what this calculator predicts for your current body weight.