TDEE & Macronutrient Calculator
Work out your basal metabolic rate, total daily energy expenditure and a protein-first macro split for your goal — in metric or imperial units.
Your body data
Required for the Katch-McArdle formula.
Results
BMR
1,728 kcal
Energy burned at complete rest.
TDEE
2,678 kcal
Maintenance calories including activity.
Target calories
2,410 kcal
Daily deficit / surplus: -268 kcal
Expected weekly change
-0.2 kg
BMR formula: Mifflin-St Jeor
Water target
2.8 L
Fibre target
34 g
Lean body mass
—
Daily macronutrients
Protein
137 g
548 kcal · 23%
Carbs
297 g
1,188 kcal · 49%
Fat
75 g
675 kcal · 28%
TDEE by activity level
| Sedentary — desk job, little exercise | 2,073 kcal |
| Light — 1–3 sessions per week | 2,375 kcal |
| Moderate — 3–5 sessions per week | 2,678 kcal |
| Active — 6–7 sessions per week | 2,980 kcal |
| Athlete — twice daily or physical job | 3,282 kcal |
Calories by goal
| Aggressive cut (−20%) | 2,142 kcal |
| Mild cut (−10%) | 2,410 kcal |
| Maintain | 2,678 kcal |
| Lean bulk (+10%) | 2,945 kcal |
| Bulk (+20%) | 3,213 kcal |
Estimates for healthy adults. Not medical advice — consult a professional before large dietary changes.
Features
- Mifflin-St Jeor and Katch-McArdle formulas
- Metric and imperial unit toggle
- Cut, maintain and lean-bulk calorie targets
- Protein-first macro presets including keto
- BMI, lean body mass, fibre and water targets
Frequently asked questions
How the maths works
Total daily energy expenditure is basal metabolic rate multiplied by an activity factor, then adjusted for your goal. Which BMR formula is more accurate depends on whether you know your body-fat percentage.
- 1Mifflin-St Jeor (men): BMR = 10 × kg + 6.25 × cm − 5 × age + 5.
- 2Mifflin-St Jeor (women): BMR = 10 × kg + 6.25 × cm − 5 × age − 161.
- 3Katch-McArdle: BMR = 370 + 21.6 × lean body mass (kg), where LBM = weight × (1 − body fat%).
- 4TDEE = BMR × activity factor (1.2 sedentary → 1.9 athlete).
- 5Target calories = TDEE × (1 + goal adjustment), never below 90% of BMR.
- 6Protein = g/kg from the chosen preset; fat = a share of total calories; carbohydrates fill the remainder (4/4/9 kcal per gram).
Activity factors are population averages and can be off by 10–15% for an individual. Track your weight for two to three weeks and adjust calories by 100–200 until the trend matches your goal.
Everything you need to know
BMR, TDEE and why the difference matters
Basal metabolic rate is what your body burns doing nothing at all: heartbeat, breathing, temperature, brain. For most people it accounts for 60–70% of total daily energy use. Total daily energy expenditure adds the rest — planned exercise, everyday movement and the energy cost of digesting food.
Eating at BMR instead of TDEE is one of the most common dieting mistakes. It creates a deficit far larger than intended, which usually ends in muscle loss, fatigue and a rebound.
Choosing the right formula
Mifflin-St Jeor is the default recommendation for the general population and needs only height, weight, age and sex. Katch-McArdle works from lean body mass instead, which makes it more accurate for lean, muscular or very heavy individuals — but only if your body-fat estimate is reliable.
If your body-fat number comes from a cheap bioimpedance scale, treat it as a rough estimate and prefer Mifflin-St Jeor. DEXA, hydrostatic weighing or careful calliper measurements justify Katch-McArdle.
Setting protein, fat and carbohydrates
Protein is set first because it is the macronutrient most strongly linked to keeping muscle in a deficit and to satiety: roughly 1.6–2.2 g per kg of bodyweight for active people, and the upper end when cutting hard.
Fat should generally stay above about 0.6 g per kg to support hormone production, and carbohydrates take whatever calories remain — they are the cheapest fuel for hard training. A keto split inverts this, pushing fat to about 70% of calories and leaving carbohydrates minimal.
- Protein: 4 kcal per gram, 1.6–2.4 g/kg depending on goal
- Fat: 9 kcal per gram, 25–35% of calories in most splits
- Carbohydrates: 4 kcal per gram, the remaining calories
- Fibre: about 14 g per 1000 kcal
How fast should the weight move?
A deficit of 500 kcal per day corresponds to roughly 0.45 kg per week, since about 7700 kcal is stored in a kilogram of body fat. Sustainable cutting usually means 0.5–1% of bodyweight per week; faster rates increase muscle loss.
For lean bulking the reverse applies: a surplus of 10% is usually enough to add tissue without excessive fat gain. Recalculate after every 3–4 kg of change, because both BMR and TDEE move with your bodyweight.