TDEE Calculator

What is TDEE?

Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a single day. It accounts for all energy expenditure — from basic biological functions at rest, to the energy used during physical activity, digestion, and daily movement.

Understanding your TDEE is the foundation of any effective nutrition plan, whether your goal is weight loss, maintenance, or muscle gain.

How TDEE is Calculated

TDEE is calculated by multiplying your Basal Metabolic Rate (BMR) by an activity factor that reflects your lifestyle:

TDEE = BMR × Activity Factor

Activity Level	Description	Multiplier
Sedentary	Desk job, little or no exercise	1.20
Lightly Active	Light exercise 1–3 days/week	1.375
Moderately Active	Moderate exercise 3–5 days/week	1.55
Very Active	Hard exercise 6–7 days/week	1.725
Extra Active	Physical job + daily exercise	1.90

The Mifflin-St Jeor Formula

We use the Mifflin-St Jeor equation (1990) to calculate BMR, which is considered the most accurate formula for most healthy adults:

Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) + 5

Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161

This formula was validated by the American Dietetic Association as the preferred method for estimating resting energy expenditure.

How to Use Your TDEE

Once you know your TDEE, you can set your calorie intake based on your goal:

• Weight loss: Eat 250–500 kcal below TDEE (loses 0.25–0.5 kg per week)
• Maintenance: Eat at TDEE to maintain current weight
• Muscle gain: Eat 250–500 kcal above TDEE (gains with minimal fat)

A deficit or surplus of 500 kcal/day corresponds to approximately 0.5 kg (1 lb) per week of weight change — the most sustainable rate recommended by health organisations.

Why TDEE Changes Over Time

Your TDEE is not fixed. It decreases as you lose weight (because a smaller body burns fewer calories) and increases as you gain muscle. This is why diet breaks or calorie cycling can be useful for long-term weight loss — they temporarily restore TDEE that has adapted downward.

Recalculate your TDEE every 4–8 weeks if your weight has changed by more than 2–3 kg.

Common Mistakes

• Overestimating activity level — the most common error. Most office workers are sedentary (1.2×), not moderately active (1.55×).
• Not accounting for metabolic adaptation — prolonged calorie restriction reduces TDEE by 10–15% below predicted values.
• Ignoring NEAT — Non-Exercise Activity Thermogenesis (fidgeting, standing, walking) can vary by 500–1000 kcal/day between individuals.

The Four Components of TDEE

TDEE is not a single number but the sum of four distinct components:

1. Basal Metabolic Rate (BMR) — 60–75% of TDEE

The calories your body burns at complete rest to maintain vital functions: heartbeat, breathing, kidney function, brain activity, and cell repair. BMR is the largest component and is driven primarily by lean body mass.

2. Thermic Effect of Food (TEF) — 8–15% of TDEE

Also called diet-induced thermogenesis, TEF is the energy cost of digesting, absorbing, and storing nutrients. Protein has the highest TEF (20–30% of its calories are "burned" in digestion), followed by carbohydrates (5–10%) and fat (0–3%). Eating more protein raises your TDEE slightly through this mechanism.

3. Exercise Activity Thermogenesis (EAT) — 5–20% of TDEE

The calories burned during planned, structured exercise: running, cycling, weightlifting, sport, etc. This is what most people think of when they think about "burning calories." For sedentary individuals, EAT is essentially zero. For high-level athletes training 2+ hours per day, it can represent 30%+ of TDEE.

4. Non-Exercise Activity Thermogenesis (NEAT) — 15–50% of TDEE

All physical activity beyond deliberate exercise — fidgeting, typing, walking to the kitchen, carrying shopping, standing at a desk. NEAT is highly variable between individuals: research from the Mayo Clinic (James Levine, 2002) found NEAT differences of up to 2,000 kcal/day between individuals of similar size. This is one of the primary reasons two people can eat the same amount and have very different weight outcomes.

Why Your TDEE May Be Higher or Lower Than Expected

TDEE calculators produce estimates that are accurate for most healthy adults within ±10%, but several factors can cause significant deviations:

Factors that increase TDEE above predicted values:

• Higher muscle mass (muscle burns ~3× more calories than fat at rest)
• High NEAT (naturally fidgety, restless, or movement-prone individuals)
• Cold climates (thermogenesis uses more energy to maintain core temperature)
• Hyperthyroidism (overactive thyroid raises BMR)

Factors that reduce TDEE below predicted values:

• Hypothyroidism (underactive thyroid reduces metabolic rate by 15–40%)
• Previous significant calorie restriction (metabolic adaptation)
• Low NEAT (extremely sedentary, limited natural movement)
• Advanced age (sarcopenia reduces muscle mass and therefore BMR)

Setting Your Calorie Targets Based on TDEE

For weight loss (fat loss with muscle preservation):

• Deficit of 250 kcal/day = ~0.25 kg/week (very slow, ideal for those close to goal weight)
• Deficit of 500 kcal/day = ~0.5 kg/week (the standard, research-supported rate)
• Deficit of 750–1,000 kcal/day = ~0.75–1 kg/week (appropriate if BMI > 30, but increases muscle loss risk)
• Never consume fewer than 1,200 kcal/day (women) or 1,500 kcal/day (men) without medical supervision

For lean muscle gain (minimising fat gain):

• A surplus of 200–300 kcal/day above TDEE
• Higher surpluses (500+ kcal) produce faster weight gain but higher fat-to-muscle ratios
• For experienced lifters, a lean bulk (200–300 kcal surplus) is typically more efficient in the long run

For body recomposition:

• Eating at TDEE or a very slight deficit (−150 to −200 kcal)
• Best suited to beginners, those returning after a break, or anyone with >20% body fat (men) or >28% (women)

Recalibrating When TDEE Predictions Don't Match Reality

If you track food accurately for 3–4 weeks and don't see expected results (≈0.5 kg/week change), adjust by 100–150 kcal in the appropriate direction and wait another 2–3 weeks before adjusting again. Your real-world TDEE is determined empirically — use the calculator as a starting estimate, then refine based on actual outcomes.

Related Resources

Related Calculators

• BMR Calculator — Calculate your basal metabolic rate at rest.
• Calorie Calculator — Plan your daily calorie intake based on weight goals.

External Authority Resources

• Mifflin-St Jeor Study on PubMed — The scientific basis for BMR calculations.
• USDA Dietary Guidelines for Americans — Federal nutrition and energy expenditure recommendations.

Sources

• Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-7.
• Frankenfield D, et al. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults. J Am Diet Assoc. 2005;105(5):775-789.
• Levine JA. Non-exercise activity thermogenesis (NEAT). Best Pract Res Clin Endocrinol Metab. 2002;16(4):679-702.