How this estimate is built
This calculator first estimates your baseline daily calorie needs using the Mifflin-St Jeor equation (a widely used resting metabolic rate formula) adjusted for your activity level, then adds the typical extra calories recommended for milk production.
Extra calories for lactation
Health guidelines commonly suggest an additional 450-500 calories per day during exclusive breastfeeding (roughly the first six months) and about 400 extra calories per day once a baby is also eating solid foods and nursing less frequently. This calculator uses 500 kcal for exclusive breastfeeding and 400 kcal for partial breastfeeding as reasonable defaults.
Individual needs vary based on milk supply, pre-pregnancy weight, weight loss goals, and overall health. This tool is for general nutrition planning and education only and is not a substitute for advice from a doctor, midwife, or registered dietitian.