Breast Milk Storage Calculator
Find out how long expressed breast milk stays safe and when to use it by. Enter the date and time you expressed the milk and choose where it's stored to get a use-by date based on standard storage guidelines.
Formula
Use-by = time expressed + the safe storage duration for the chosen location
- Room temperature (≤ 25°C): use within about 4 hours for best quality (up to 6 if very clean).
- Insulated cooler with ice packs: up to about 24 hours.
- Refrigerator (4°C): up to about 4 days is best (5–8 days if hygiene is excellent).
- Freezer (−18°C): up to about 6 months for best quality, acceptable to 9 months.
- Thawed milk should be used within 24 hours and never refrozen. These are general guidelines — follow your healthcare provider's advice.
Milk expressed Jan 1, stored in the fridge
Inputs
- Date & time expressed: 2026-01-01
- Storage location: fridge
Milk refrigerated at 4°C is best used within about 4 days, so milk expressed on 1 January should be used by around 5 January.
Frequently asked questions
How long does breast milk last in the fridge?
Up to about 4 days at 4°C for best quality, and 5–8 days if it was expressed and stored under very clean conditions.
How long can breast milk stay at room temperature?
About 4 hours is ideal at up to 25°C, extending to roughly 6 hours when expressed very hygienically.
Can I refreeze thawed breast milk?
No. Once thawed, use the milk within 24 hours and never refreeze it.
Are these times exact?
They are general storage guidelines. Always check your local health authority's advice and your baby's specific needs.
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