How your calorie needs are calculated
This calculator first estimates your Basal Metabolic Rate (BMR) — the calories your body burns at complete rest — using the Mifflin-St Jeor equation, widely regarded as one of the more accurate BMR formulas. It then multiplies BMR by an activity factor to estimate your Total Daily Energy Expenditure (TDEE), the calories you burn in a typical day including movement and exercise.
Choosing the right activity level
Be honest about your activity level — overestimating it is one of the most common reasons calorie targets don't lead to expected results. "Moderate activity" means structured exercise 3-5 days a week, not just an active job or occasional walks.
Calorie deficit and surplus for weight goals
A deficit of about 500 calories/day is a commonly used target for gradual weight loss (roughly 0.5kg/week), while a similar surplus supports gradual weight gain. Very large deficits or surpluses are generally not sustainable or healthy long-term.
Frequently asked questions
Is this accurate for everyone? It's a population-average estimate — individual metabolism can vary by 10-15% due to genetics, muscle mass, and other factors. Use it as a starting point and adjust based on real-world results.
Should I eat back exercise calories? The activity multiplier already accounts for regular exercise, so you generally don't need to add calories back for workouts already reflected in your activity level.