Infant Calorie Needs

How it is calculated

The tool multiplies the baby's weight by one fixed energy rate: calories (kcal/day) = weight (kg) × 100. Weight is in kilograms and 100 is the kcal per kilogram per day. The result is rounded to a whole number. The same 100 kcal/kg is used for every baby, so it does not change with age, prematurity, illness or the way the baby is fed, and it does not reflect how the per-kilogram need shifts over the first year. The 100 is a mid-range planning figure, not a measurement. Weights below 0.3 kg or above 20 kg give no result, since they are outside the infant range. The answer is total energy, not millilitres of milk, so you still need to convert it to the volume your baby takes, and it does not replace a growth-chart check.

Common mistakes

• Entering weight in grams or pounds. The field is kilograms, so 6,500 g is entered as 6.5; typing 6500 gives no result.
• Reading the answer as millilitres of milk. It is calories; milk volume depends on how many calories each 30 mL provides.
• Using the same number for the whole first year. The tool applies 100 kcal/kg at every weight, while real needs per kilogram change as the baby grows.
• Treating the figure as a target to push the baby towards. Babies regulate their own intake, so use it as a check against what the baby takes, not as an order.
• Using it for an older child or a toddler. Weights above 20 kg are rejected, and the flat 100 kcal/kg is meant for infants only.