Preparedness & Self-Reliance Tool

72-Hour Emergency Kit Calculator

Enter your household size and get precise supply quantities, water, food, and essentials, for a complete 72-hour emergency kit.

Calculate your 72-hour kit supplies

Enter your household details to get personalized quantity recommendations.

Household & conditions

People aged 13 and over.
Children aged 2–12.
Dogs and cats (average weight assumed).
Live results update as you type
72-Hour Kit Requirements

9.0 gallons water

For 2 adults + 1 child + 1 pet, moderate, temperate.

9.0 gal Water (drinking + sanitation)
18,900 cal Total calories (72 hrs)
3 People covered

How to use this calculator

Enter the number of adults, children, and pets in your household. Select your likely activity level during an emergency and the expected climate conditions. The calculator outputs total water needs in gallons, calorie requirements for 72 hours, and a per-person breakdown. Use the results as a shopping checklist when purchasing supplies.

Tips for success

  • Add a 20-30% buffer over the FEMA minimum. 1 gallon of water per person per day is the baseline. Hot weather, physical exertion, or illness can double that need.
  • Pick shelf-stable foods your family already eats. Stress suppresses appetite for unfamiliar foods. Rotate kit contents every 6-12 months so nothing expires unused.
  • Include a manual can opener. Sounds obvious, but it is frequently forgotten when assembling kits from scratch.
  • Laminate a prescription card. Document medications and dosages on a card inside the kit. Many people evacuate without their list and struggle to get refills at shelters.
  • Use a wheeled bag or tote if possible. An adult carrying a heavy backpack cannot also assist children, elderly relatives, or pets at the same time.
The 72-hour target comes from emergency management guidance that outside assistance is often delayed for the first 72 hours after a major disaster. Some experts now recommend a 2-week kit. Multiply these quantities by 4.7 to estimate a full 2-week supply.

Essential categories for a 72-hour kit

  • Water: 1 gallon per person per day minimum. Include water purification tablets as a backup. Store in food-grade containers away from direct sunlight.
  • Food: MREs, freeze-dried meals, protein bars, canned goods, peanut butter, crackers. Aim for 1,800–2,500 calories per adult per day depending on activity level.
  • First aid: Bandages, antiseptic, tourniquet, OTC medications (pain reliever, antidiarrheal, antihistamine), and any personal prescriptions with a 3-day supply.
  • Light and communication: Flashlight with extra batteries, hand-crank or battery radio, portable phone charger. A signal whistle is small and can be life-saving.
  • Documents and cash: Copies of IDs, insurance cards, emergency contacts in a waterproof bag. Keep small bills, card readers may not work after a disaster.
  • Shelter and warmth: Emergency mylar blankets, rain poncho, sturdy walking shoes. Even in warm climates, wet conditions and night temperatures can cause hypothermia.

FAQ

How much water per person per day is actually needed?

FEMA's baseline of 1 gallon covers approximately 64 oz of drinking and 64 oz for basic sanitation. In hot weather or heavy activity, drinking needs alone can reach 96–128 oz. Plan for 1.5 gallons per active adult in summer conditions to be safe.

How many calories does each person need for 72 hours?

Sedentary adults sheltering in place need roughly 1,600–2,000 calories per day. Active adults evacuating need 2,500–3,500 calories. Children need 1,200–2,000 calories depending on age. During high-stress situations, calorie-dense, easy-to-open foods are preferred over items requiring preparation effort.

How much water do pets need?

Dogs and cats typically need approximately 1 ounce of water per pound of body weight per day. A 50-lb dog needs roughly 0.4 gallons daily. The calculator uses an average pet weight estimate, adjust for very large dogs or multiple animals.

Should my kit be a bag or a bin?

Both serve different purposes. A backpack or duffel is essential for evacuation mobility. A larger plastic bin is better for shelter-in-place kits. Many experts recommend both: a grab-and-go bag for immediate evacuation plus a larger home cache for extended sheltering in place.

How often should I rotate and update my kit?

Check water containers annually. Rotate food every 6–12 months by consuming and replacing with fresh stock. Inspect batteries twice a year. Replace expired medications. A simple habit is to audit the kit at daylight saving time changes, the same schedule used for smoke alarm batteries.