# Breastfeeding Calorie Calculator

URL: https://speedycalculator.com/calculators/health/breastfeeding-calorie/
Last updated: 2026-10-30

> The breastfeeding calorie calculator estimates how many calories you need while breastfeeding: your usual maintenance calories (Mifflin–St Jeor) plus the extra energy for milk production, which depends on your baby's age and how much they breastfeed.

## Inputs

- Age (years)
- Weight (kg, lb, st, g)
- Height (cm, in, m, ft, mm)
- Activity level
- Baby's age
- Feeding

## Results

- BMR
- Maintenance calories before breastfeeding
- Extra for breastfeeding
- Daily calories while breastfeeding
- Do not go below

## Formula

```
Maintenance = BMR (Mifflin–St Jeor) × activity factor
Extra for exclusive breastfeeding: +330 kcal (0–6 months), +400 kcal (7–12 months)
Partial breastfeeding: about half the extra
```

## Explanation

Making breast milk uses about 500 kcal a day in the first six months. Part of this comes from fat stored during pregnancy, so the recommended extra intake is about 330 kcal. Losing weight gradually, up to about 0.5 kg (1 lb) a week, does not usually affect milk supply.

### How to use the Breastfeeding Calorie Calculator

- **Age**
- **Weight**
- **Height**
- **Activity level**
- **Baby's age**
- **Feeding**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter your details, activity level, your baby's age and how you are feeding.

### Inputs explained

FieldWhat to enterAgeIn yearsWeightUnits: kg, lb, st, gHeightUnits: cm, in, m, ft, mmActivity levelChoose one: Sedentary, Lightly active, Moderately active, Very activeBaby's ageChoose one: 0–6 months, 7–12 monthsFeedingChoose one: Exclusive breastfeeding, Partial (breast milk and formula or solids)

### What each result means

- **BMR** = 10×[Weight] + 6.25×[Height] - 5×[Age] - 161
- **Maintenance calories before breastfeeding** = [BMR]×[Activity level]
- **Daily calories while breastfeeding** = [Maintenance calories before breastfeeding] + [Extra for breastfeeding]
- **Do not go below** = 1800

### Example values

How the main result changes when **Age** changes and everything else stays at the example values above:

Age (years)Daily calories while breastfeeding (kcal/day)152,35822.52,307302,25537.52,204452,152
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Age: 30 years; Weight: 68 kg; Height: 165 cm; Activity level: Lightly active; Baby's age: 0–6 months; Feeding: Exclusive breastfeeding.

Results — BMR = 1,400 kcal/day; Maintenance calories before breastfeeding = 1,925 kcal/day; Extra for breastfeeding = 330 kcal/day; **Daily calories while breastfeeding = 2,255 kcal/day**; Do not go below = 1,800 kcal/day.

## Key terms

- **Exclusive breastfeeding**: Only breast milk, no formula or solids.

## FAQ

**How many extra calories does breastfeeding need?**
About 330–400 kcal a day on top of your usual needs.

**Can I diet while breastfeeding?**
Gradual weight loss is fine; avoid going below about 1,800 kcal a day.

**Do I need to drink more?**
Drink to thirst – many mothers find a glass of water at each feed helpful.


## Sources

- [Institute of Medicine – Dietary Reference Intakes for Energy (2005)](https://nap.nationalacademies.org/catalog/10490/)
- [CDC – Maternal diet and breastfeeding](https://www.cdc.gov/breastfeeding-special-circumstances/hcp/diet-micronutrients/maternal-diet.html)