Calorie Intake Calculator
How many calories does your body actually need each day?
About Calorie Intake Calculator
Your daily calorie intake need is your Total Daily Energy Expenditure (TDEE) — the sum of your Basal Metabolic Rate and all physical activity — adjusted for your weight goal. This calculator uses the Mifflin-St Jeor equation (the most accurate BMR formula for the general population) multiplied by your activity level, then applies a WHO-aligned deficit or surplus to generate your personalised daily target. The result also includes a macronutrient breakdown following WHO dietary guidelines: 50% carbohydrates, 20% protein, 30% fat.
Step 1 — BMR (Mifflin-St Jeor): Male: 10×W + 6.25×H − 5×A + 5 Female: 10×W + 6.25×H − 5×A − 161 Step 2 — TDEE: BMR × Activity Factor (1.2 – 1.9) Step 3 — Goal Adjustment: Lose fast: TDEE − 1,000 kcal (−1 kg/week) Lose: TDEE − 500 kcal (−0.5 kg/week) Maintain: TDEE ± 0 Gain: TDEE + 500 kcal (+0.5 kg/week) Gain fast: TDEE + 1,000 kcal (+1 kg/week)
Source: Mifflin MD et al., 1990 — Am J Clin Nutr · WHO/FAO/UNU Human Energy Requirements Report (2004) · WHO Healthy Diet Fact Sheet (2024) · U.S. Dietary Guidelines 2020–2025
Why Your Calorie Target Matters
Chronic energy imbalance — in either direction — is the root cause of most preventable metabolic disease. Your daily calorie target is not just a weight number; it is the foundation of your hormonal health, metabolic rate, and long-term wellbeing.
Sustained Overconsumption
Consistently eating above TDEE drives fat accumulation, insulin resistance, and chronic low-grade inflammation — the shared pathway to type 2 diabetes, cardiovascular disease, and metabolic syndrome. Even a modest 200–300 kcal daily surplus compounds significantly over months.
Sustained Underconsumption
Eating below your BMR forces the body to break down muscle for energy and lower its metabolic rate — making future fat loss progressively harder. Chronic undereating disrupts cortisol, thyroid hormones, and reproductive function. WHO identifies severe dietary restriction as a direct cause of malnutrition even in high-income populations.
Calorie Quality vs. Quantity
Equal calorie amounts do not produce equal metabolic effects. 500 kcal from whole grains, lean protein, and vegetables triggers a very different hormonal response than 500 kcal from refined sugar and processed fat. WHO recommends deriving calories from nutrient-dense whole foods, limiting free sugars to less than 10% of total energy intake.
How to Use Your Calorie Target Most Effectively
A calorie target is a starting estimate, not a fixed prescription. Understanding how to apply it gives you far better long-term results than following a number rigidly:
Your TDEE is an estimate — adjust based on real results
Calorie calculators are accurate within ±10% for most people. Track your weight over 2–3 weeks at your target intake. If you are not seeing the expected change (roughly 0.5 kg/week), adjust by 100–200 kcal in the appropriate direction. Real-world feedback is more reliable than any formula.
Pair calorie targets with macronutrient quality
WHO recommends 45–75% of calories from carbohydrates, 10–15% from protein, and 15–30% from fat — prioritising whole grains, lean proteins, and unsaturated fats. Hitting your calorie number with poor food quality undermines hormonal health, satiety, and muscle preservation even when the number is correct.
Recalculate as your body changes
As you lose or gain weight, your BMR and TDEE shift. Recalculate every 4–6 weeks or after every 3–5 kg of body weight change. Stalling on a weight loss plan is almost always a sign that your TDEE has decreased and your target needs downward adjustment.