Ready.gov recommends at least one gallon of water per person per day. This is a planning aid, not medical advice; adjust for climate, health, pets, and dietary needs.
Meals or servings needed
84
Water needed
28.0 gal
Missing servings
64
Missing water
23.0 gal
Quick answer: Multiply household members by daily servings per person by planning days to get total servings needed, then subtract usable shelf-stable food already on hand. Ready.gov recommends at least three days for evacuation and two weeks for sheltering in place.
Practical guide
How to estimate an emergency food and water gap
- 1
Choose the number of people and planning days.
- 2
Enter planned daily servings and water per person, then account for pets and special needs separately.
- 3
Subtract usable supplies already on hand and build the remaining gap gradually.
Worked example
Example: Four people planning for three days at three food servings per person per day need 36 servings before subtracting existing supplies.
How to read the result
The result is a quantity gap, not a complete emergency plan. Favor familiar, usable foods and follow current local emergency instructions.
Important limits: Medical needs, infants, pets, climate, cooking access, water treatment, and local hazards require individual planning. Official guidance takes priority.
Evergreen method
Measure how much of the basket had a job
A useful list connects purchases to meals, staples or a deliberate reserve before checkout.
Formula
planned coverage = planned items ÷ total items × 100Reproducible steps
- 1.Inventory what you already have.
- 2.Give each planned item a meal, staple or reserve role.
- 3.Review unplanned items before checkout instead of banning them blindly.
Data note — Evergreen model: The formula works with your own inputs and does not depend on a specific price or year.
FAQ
Questions, answered
How much emergency food should I store?
Plan from household size, number of days, and normal dietary needs, then follow current Ready.gov and local emergency guidance.
Does the calculator include water?
Yes, as a planning input. Adjust for heat, illness, pregnancy, pets, and local official recommendations.
Should I buy everything at once?
Not necessarily. Build a rotating supply of familiar shelf-stable items your household already uses, while watching dates and storage conditions.
What is the best emergency food to stock at home?
Shelf-stable items your household actually eats: canned beans, canned fish, rice, oats, peanut butter, crackers, and dried fruit. Familiar foods reduce stress in an emergency and rotate naturally into your regular grocery shopping. The Emergency Food Supply Calculator above shows the total servings and water you need for any household size and number of days.
How many days of food should I have stored at home?
Ready.gov recommends a minimum of three days for evacuation scenarios and two weeks for sheltering in place. Enter your household size and target days above to calculate the exact number of servings and gallons of water needed, minus what you already have on hand.
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