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Child’s Daily Calorie Need

Children need far more calories per kilogram than adults, and the figure falls as they grow — from around 100 kcal/kg near their first birthday down to the adult 35–40 by adolescence.

Your numbers

Daily calorie need

1,580kcal

Calories per kg

79kcal

Protein

22g

Formula

Daily calorie need = Weight (kg) × (100 − Age × 3.5)

Very active children need 20–30% more. Tracking along their growth curve is the surest sign the intake is right.

What to enter

InputDefaultAccepted range
Weight (kg) (kg)The second weight you are comparing against.201 ~ 80
AgeAge in completed years — it shifts by one depending on the birthday.60 ~ 18

Step by step

FormulaDaily calorie need = Weight (kg) × (100 − Age × 3.5)
With the default numbersDaily calorie need = 20 × (100 − 6 × 3.5)
AnswerDaily calorie need = 1,580 kcal

Quick reference table

Results when only Weight (kg) (kg) changes and everything else stays put.

Weight (kg) (kg)Daily calorie need (kcal)Calories per kg (kcal)Protein (g)
107907911
151,1857916.5
201,5807922
302,3707933
403,1607944

What each result means

ResultAt default values
Daily calorie need (kcal)A child’s daily calories; the per-kilogram figure falls with age.1,580
Calories per kg (kcal)Calories burned per kilogram — how briskly your metabolism runs.79
Protein (g)Grams of protein for the day; each gram is 4 kcal.22

Common mistakes

Very active children need 20–30% more. Tracking along their growth curve is the surest sign the intake is right.

Glossary

Weight (kg)
The second weight you are comparing against.
Age
Age in completed years — it shifts by one depending on the birthday.
Daily calorie need
A child’s daily calories; the per-kilogram figure falls with age.
Calories per kg
Calories burned per kilogram — how briskly your metabolism runs.
Protein
Grams of protein for the day; each gram is 4 kcal.

Frequently asked questions

Q. How is Child’s Daily Calorie Need calculated?

Daily calorie need = Weight (kg) × (100 − Age × 3.5) — Children need far more calories per kilogram than adults, and the figure falls as they grow — from around 100 kcal/kg near their first birthday down to the adult 35–40 by adolescence.

Q. Can you walk through an example?

With Weight (kg) 20kg, Age 6, the answer is Daily calorie need 1,580kcal.

Q. What do I need to enter?

Enter Weight (kg), Age. The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Weight (kg) (kg) moves the answer to Weight (kg) (kg) 10 → Daily calorie need (kcal) 790 and Weight (kg) (kg) 40 → Daily calorie need (kcal) 3,160. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

Very active children need 20–30% more. Tracking along their growth curve is the surest sign the intake is right.

Related calculators

These calculators help you understand health figures; they do not replace diagnosis or prescription. See a clinician if you have symptoms.