Emergency supply calculator

Enter your household and how long you want to be covered. The totals update as you go.

Reviewed October 2026

How the numbers are worked out

• Water: one gallon per person per day, for drinking, cooking and basic hygiene. This is the amount the CDC and FEMA recommend.
• Cases of bottled water: based on the common 24-bottle case of 16.9-ounce bottles, which holds about 3.17 gallons. The total is rounded up.
• Meals: three per person per day, using food that keeps without a fridge.

Which length to choose

• 3 days is the minimum to keep at home, and about what fits in a go bag if you have to leave.
• 14 days is what the CDC suggests storing at home if you have space. It gives you a cushion if stores and water service are slow to recover after a major storm.

Adjust for your household

Store more water in hot weather, and for anyone who is pregnant or sick. Pets need their own food and water on top of these totals. If anyone takes daily medication, ask your doctor or pharmacist about keeping an extra supply.

Next, see how to store water safely, what food to stock, and the full emergency kit checklist.