TDEE Calculator

What Is TDEE and Why Does It Matter?

The TDEE calculator computes your Total Daily Energy Expenditure — every calorie your body burns in 24 hours, including rest, digestion, and exercise. With 450,000 monthly searches, this is one of the most-searched nutrition tools online. TDEE is your true maintenance calorie level: eat at TDEE and your weight is stable; eat less and you lose weight; eat more and you gain.

TDEE consists of four components: BMR (60–70%), TEF (Thermic Effect of Food, 10%), EAT (Exercise Activity Thermogenesis, 5–25%), and NEAT (Non-Exercise Activity Thermogenesis — fidgeting, walking, standing — 15–50%). NEAT varies dramatically between individuals and is why two people with identical BMRs can have very different TDEEs.

How Many Calories Should I Eat? TDEE by Goal

• Fat loss (moderate cut): TDEE − 500 cal/day = approximately 1 lb/week loss. Sustainable with adequate protein.
• Aggressive cut: TDEE − 750 to −1,000 = 1.5–2 lbs/week. Requires 0.8–1g protein/lb bodyweight to preserve muscle.
• Maintenance: Eat at TDEE ± 100 calories. Weight will fluctuate 1–3 lbs daily from water and food volume.
• Lean bulk: TDEE + 200–300 = slow muscle gain with minimal fat.
• Recomposition: Eat at maintenance. Loses fat and gains muscle simultaneously — works best for beginners.

Maintenance Calories Calculator: Mifflin-St Jeor Equation

This calculator uses the Mifflin-St Jeor equation, the most validated BMR formula in clinical nutrition (within ±10% for 82% of people in validation studies):

• Men: BMR = 10W + 6.25H − 5A + 5 (W=kg, H=cm, A=age)
• Women: BMR = 10W + 6.25H − 5A − 161

TDEE = BMR × Activity Multiplier: Sedentary (1.2), Light (1.375), Moderate (1.55), Heavy (1.725), Athlete (1.9). Most people choose too high an activity level — go one level lower if unsure.

Calorie Calculator to Lose Weight: Real Examples

• 25-year-old man, 180 lbs, 5'10", moderate exercise: BMR ~ 1,932 kcal. TDEE ~ 2,995 kcal. Cut target: 2,495 kcal/day.
• 32-year-old woman, 140 lbs, 5'5", light exercise: BMR ~ 1,426 kcal. TDEE ~ 1,961 kcal. Cut target: ~1,461 kcal/day.
• 45-year-old man, 220 lbs, 6'1", sedentary: BMR ~ 2,045 kcal. TDEE ~ 2,454 kcal. Cut target: 1,954 kcal/day.

Frequently Asked Questions

Why does TDEE decrease when I lose weight?

Two reasons: (1) smaller body = lower BMR, and (2) metabolic adaptation — the body becomes more efficient and downregulates NEAT and hormones in response to prolonged caloric restriction. Recalculate your TDEE every 10–15 lbs of weight change and adjust intake accordingly. Many people plateau not because they "broke" their metabolism but because they haven't adjusted for their now-lighter body.

How accurate are TDEE calculators?

Typically ±10–15% for most people. If your calculated TDEE is 2,500 kcal, your actual TDEE is likely 2,125–2,875 kcal. The only way to determine your real TDEE is empirically: track food intake at a consistent calorie level for 2–3 weeks while weighing yourself daily. Use the calculator as a starting point, then refine based on actual results.

TDEE Calculator: Comparing TDEE Formulas

Several formulas exist for estimating BMR and TDEE. The major options:

• Mifflin-St Jeor (1990): Used by this calculator. Most validated in clinical research. Accuracy within ±10% for 82% of subjects in validation studies. Best choice for most users.
• Harris-Benedict (revised 1984): Older formula that slightly overestimates BMR compared to Mifflin-St Jeor. Still used in many clinical settings. Underperforms Mifflin-St Jeor on average.
• Katch-McArdle: Uses lean body mass (LBM) instead of total weight, making it more accurate for very muscular or very obese individuals. Requires knowing body fat percentage: BMR = 370 + (21.6 × LBM in kg). Most accurate when LBM is known from DEXA or hydrostatic weighing.
• Cunningham: Also LBM-based. Popular among athletes and bodybuilders who have accurate body composition measurements.

For the average person without precise body composition data, Mifflin-St Jeor is the best choice. For athletes and those with known body fat percentage, Katch-McArdle may be more accurate. The real-world difference between formulas is typically 50–150 calories/day — less than the margin of error from activity level selection.

Important caveat: all TDEE calculators, regardless of formula, are estimation tools. Individual metabolic variation, thyroid function, gut microbiome, habitual NEAT, and sleep quality all affect actual TDEE in ways no formula can capture. Treat the output as a hypothesis to test empirically, not a definitive answer.

TDEE Calculator: Special Populations and TDEE Adjustments

Standard TDEE formulas are less accurate for certain populations. Adjustments to consider:

• Very muscular individuals: Standard formulas underestimate TDEE because muscle tissue is more metabolically active than fat tissue. Use the Katch-McArdle formula (requires knowing lean body mass) for bodybuilders and athletes with very low body fat percentage.
• Very obese individuals: Standard formulas may overestimate TDEE. The Mifflin-St Jeor equation performs reasonably well up to BMI 40, but accuracy decreases further. Use actual measured TDEE (empirical approach) when precision matters.
• Elderly (65+): TDEE decreases with age beyond what height/weight/activity formulas capture. Sarcopenia (muscle loss with aging) reduces BMR; reduced mobility decreases NEAT. Standard formulas may overestimate by 100–200 calories/day for sedentary elderly individuals.
• Pregnant and breastfeeding: Pregnancy adds ~300 kcal/day in the second and third trimesters. Breastfeeding adds ~500 kcal/day. Standard TDEE formulas are not appropriate during pregnancy — consult OB/GYN for caloric guidance.
• Medical conditions affecting metabolism: Hypothyroidism dramatically reduces metabolic rate — diagnosed hypothyroid individuals may have TDEE 20–30% below formula predictions before treatment. Other conditions affecting metabolism include Cushing's syndrome, PCOS, and certain medications (beta-blockers, steroids).