TDEE Calculator: Mifflin, Harris-Benedict, Cunningham, Oxford, Macro & Reverse TDEE Guide
What is Total Daily Energy Expenditure (TDEE)?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in 24 hours — including Basal Metabolic Rate (BMR), the thermic effect of food (TEF, ~10% of calories), exercise activity thermogenesis (EAT), and non-exercise activity thermogenesis (NEAT).
TDEE is the cornerstone of evidence-based nutrition: knowing your TDEE tells you exactly how many calories you need to maintain, lose, or gain weight. It is calculated as BMR × Physical Activity Level (PAL) multiplier using WHO/FAO/UNU 2004 guidelines.
This calculator implements all four major BMR equations (Mifflin-St Jeor, Harris-Benedict, Cunningham, Oxford) plus three application modes: Macro Calculator, Weight Goal Planner, and Reverse TDEE.
The 4 TDEE BMR Formulas
Mifflin-St Jeor (1990) — AND/ACSM Gold Standard
Female: BMR = 10×W(kg) + 6.25×H(cm) − 5×Age − 161
Validated against 498 subjects via indirect calorimetry. Recommended by AND and ACSM as the most accurate for general adults. Error: ±10% for most individuals.
Harris-Benedict Revised (Roza & Shizgal 1984) — WHO/Clinical Standard
Female: BMR = 447.593 + 9.247×W + 3.098×H − 4.330×Age
The 1919 original revised by Roza & Shizgal using 337 subjects. The WHO/clinical-research standard. Slightly overestimates BMR in obese individuals.
Cunningham (1980) — ISSN Athlete Formula
Uses lean body mass directly — most accurate for athletes and individuals with measured body fat %. Endorsed by the International Society of Sports Nutrition (ISSN).
Oxford Equations (Elia & Livesey 2005) — WHO Weight-Only
Male 30–59: BMR = 11.472×W + 873.1
Male 60+: BMR = 11.711×W + 587.7
Female 18–29: BMR = 13.623×W + 630.0
Female 30–59: BMR = 9.740×W + 694.4
Female 60+: BMR = 10.075×W + 577.9
Requires only weight — no height — and is validated across diverse world populations in the WHO 2005 technical report. Particularly useful in clinical and field settings where height is unavailable or unreliable.
7 Calculator Modes Explained
- Mifflin-St Jeor TDEE — 5 fields. AND/ACSM gold standard. BMR × PAL with all activity levels shown.
- Harris-Benedict TDEE — 5 fields. WHO/clinical standard. Outputs BMR, TDEE, BMI, and all 5 PAL levels.
- Cunningham TDEE — 3 fields (weight, body fat %, activity). LBM-based RMR — most accurate for athletes. Shows lean mass, fat mass, and all PAL levels.
- Oxford Equations TDEE — 4 fields (weight, age, sex, activity). Weight-only formula, no height. Validated across world populations.
- Macro Calculator — 7 fields. TDEE ± goal adjustment converted to protein/carbs/fat targets. 5 evidence-based diet styles available.
- Weight Goal Planner — 7 fields. Calculates days/weeks/months to goal weight at your chosen rate of change (0.25–1.0 kg/week). Shows daily calorie target.
- Reverse TDEE — 4 fields. Back-calculates your actual TDEE from start/end weight, tracking duration, and average intake. Best with 4+ weeks of data.
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Physical Activity Level (PAL) Multipliers — WHO/FAO/UNU 2004
| Activity Level | PAL | Description |
|---|---|---|
| Sedentary | ×1.2 | Desk job, little/no exercise |
| Lightly Active | ×1.375 | Exercise 1–3 days/week |
| Moderately Active | ×1.55 | Exercise 3–5 days/week |
| Very Active | ×1.725 | Hard exercise 6–7 days/week |
| Extra Active | ×1.9 | Physical job + daily training |
NEAT (non-exercise activity thermogenesis — fidgeting, standing, walking) accounts for 200–800 kcal/day variation between individuals. Accurate activity classification is the most important variable after BMR. Most people overestimate their activity level by one category.
Macro Splits & Diet Styles
| Diet Style | Protein | Carbs | Fat | Source |
|---|---|---|---|---|
| Balanced | 30% | 40% | 30% | ACSM 2016 |
| High Protein | 40% | 30% | 30% | ISSN 2017 |
| Low Carb | 30% | 25% | 45% | General |
| Ketogenic | 25% | 5% | 70% | Volek & Phinney |
| High Carb | 20% | 60% | 20% | IOC 2011 |
Protein: 4 kcal/g · Carbohydrates: 4 kcal/g · Fat: 9 kcal/g. During fat loss, maintain protein at ≥1.6–2.2 g/kg body weight to preserve lean mass (Phillips & Van Loon 2011). For endurance athletes, the High Carb split supports glycogen replenishment per IOC 2011 consensus.
Reverse TDEE: Back-Calculate Your Actual Maintenance Calories
Formula-based TDEE estimates can miss your actual metabolic rate by 10–20% due to individual variation, metabolic adaptation, or inaccurate activity classification. The Reverse TDEE method uses your own weight-change and intake data to calculate your true TDEE directly:
Example: Ate 1,800 kcal/day for 28 days, lost 1.5 kg → Daily balance = −1.5 × 7,700 ÷ 28 = −412.5 kcal/day → TDEE = 1,800 + 412.5 = 2,212 kcal/day.
Best results require 4–12 weeks of consistent food logging and daily weigh-ins (averaged weekly). Short periods (<2 weeks) are skewed by water retention from carbohydrate and sodium fluctuations. Very small weight changes (<0.3 kg) may be within scale measurement error.
FAQs
Why does my TDEE differ between formulas?
Each BMR equation was derived from a different study population with different body compositions, age ranges, and measurement techniques. A spread of 50–100 kcal between Mifflin and Harris-Benedict is typical. Larger spreads (>150 kcal) usually indicate atypical body composition — very lean, very obese, or very muscular — where any formula based on weight/height proxies will diverge. The Cunningham formula avoids this by using lean body mass directly.
Is TDEE the same every day?
No. TDEE fluctuates daily by 200–500 kcal depending on activity level, sleep, hormonal cycles, and NEAT. The PAL multiplier gives a weekly average. For this reason, weekly calorie budgets (TDEE × 7) are more practical than strict daily targets — eating at maintenance on rest days and slightly above on training days averages out similarly.
How accurate is the Reverse TDEE method?
With 4–12 weeks of consistent tracking and a weight change of ≥0.5 kg, the Reverse TDEE method estimates true maintenance calories within ±100–150 kcal — substantially better than formula predictions alone. Accuracy depends entirely on the honesty of food logging (most people underreport by 10–20%) and using averaged weekly weights to filter out water fluctuations.