How to Calculate Breast Milk Intake
What is Breast Milk Intake?
A breast milk calculator estimates how much milk a baby needs per day and per feed. Adequate wet nappies (6+/day) and weight gain are the best indicators of sufficient intake.
Formula
Output estimate = 150 mL/kg/day typical by day 5–7 (e.g., 3.5 kg baby = 525 mL/day); Increases gradually to 750–900 mL/day month 1–6
- BabyWeight
- Baby body weight (kg)
- DailyOutput
- Daily milk production (mL)
- DayPostBirth
- Days postpartum (Integer (1–180))
Step-by-Step Guide
- 1Newborns: ~150 mL/kg/day
- 2From ~4–6 weeks: ~120 mL/kg/day
- 3Divide daily total by number of feeds
- 4Demand feeding is normal — amounts vary feed to feed
Worked Examples
Input
5 kg baby, 2 months, 7 feeds/day
Result
Daily ≈ 600 mL; per feed ≈ 86 mL
Frequently Asked Questions
How do I know if baby is getting enough?
6+ wet diapers, 2–5 dirty diapers/day (day 2+). Weight check: back to birth weight by day 10–14, gain 15–30 g/day month 1–3. Healthcare provider monitors.
What affects milk supply?
Frequent feeding (8–12x/day month 1) stimulates supply. Dehydration, stress, poor latch reduce it. Medications (some), retained placenta increase risk of low supply.
Is pumping output = actual feeding output?
No. Pumps less efficient than baby at extracting milk. Baby + pump output > pump alone. Use baby's feeding patterns (wet diapers, weight) to assess adequacy.
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