Calorie Calculator

Weight change follows sustained energy balance. Roughly 7,700 kilocalories correspond to a kilogram of body tissue, so a daily gap of about 550 kcal shifts half a kilo per week. The calculator applies your chosen pace directly to estimated maintenance needs. Under the hood, basal metabolic rate comes from the Mifflin-St Jeor equation — the formula most dietetics references prefer for adults — multiplied by an activity factor from 1.2 (sedentary) to 1.9 (extremely active) to estimate total daily energy expenditure (TDEE).

Pacing matters more than ambition. Aggressive deficits sacrifice muscle, adherence and sanity; moderate ones survive contact with real life. Research on weight-loss maintenance consistently finds that faster initial loss predicts faster regain when the method is unsustainable, while 0.25–0.75 kg per week lets habits, training and social eating coexist with the plan. The tool flags targets that fall beneath your BMR, where professional guidance becomes genuinely important — chronically eating below basal needs risks nutrient deficiency, hormonal disruption and muscle loss.

Activity level is where most people mis-estimate. 'Moderately active' means deliberate exercise most days plus a non-sedentary daily life — not a desk job with three gym visits. When in doubt, pick one level lower than your ego suggests, run the numbers for two weeks, and adjust from the scale trend. Overestimating activity by one tier inflates the target by 200–400 kcal, silently erasing a deficit.

Protein and resistance training decide what kind of weight you lose. In a deficit, commonly cited guidance suggests roughly 1.6–2.2 g of protein per kilogram of body weight daily plus 2–4 weekly strength sessions to preserve lean mass — the tissue that keeps metabolism, strength and appearance intact. Two people losing 10 kg can look and feel dramatically different depending on whether 8 kg or 3 kg of it was fat.

Plateaus are normal physiology, not failure. As you get lighter, TDEE falls (a smaller body burns less), and adaptive thermogenesis trims expenditure further — often 100–300 kcal beyond what the smaller size alone predicts. When loss stalls for 3+ weeks, the evidence-backed responses are: re-verify tracking accuracy (oils, drinks, bites and weekend meals are the classic leaks), add steps or training volume, or take a 1–2 week diet break at maintenance before resuming — not slashing another 500 kcal in frustration.

Finally, treat any calculator output as a starting hypothesis. Metabolism varies with genetics, medications, thyroid function, sleep, stress and history of dieting. Run the estimate, follow it consistently for 2–4 weeks, compare against the scale's moving average, then adjust intake by 100–200 kcal at a time. For medical conditions, pregnancy, adolescence or targets below BMR, involve a clinician or registered dietitian — general information here, not medical advice.