Water Supply Calculator

Calculate exactly how much emergency water your household needs based on family size, pets, climate, and duration.

Hot climates or summer months increase water needs by up to 50%
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Your Water Supply Requirements

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Total Gallons
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Total Liters
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Total Weight (lbs)

Daily Breakdown

Storage Recommendations

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    How We Calculate Water Needs

    Our calculator follows FEMA and the American Red Cross guidelines, which recommend one gallon (3.78 liters) per person per day as a baseline. This covers both drinking water (approximately half a gallon) and sanitation needs (washing, cooking, hygiene).

    Hot climates can increase consumption by 50% due to higher perspiration and dehydration risk. Nursing mothers, individuals with medical conditions, and those performing heavy physical labor also require additional water. Children's needs are calculated at 75% of adult consumption.

    For dogs, we use 1 ounce of water per pound of body weight per day (estimated at 0.5 gallons for an average-sized dog). Cats require approximately 0.25 gallons per day.

    Learn more about emergency water management in our guide: 5 Essential Water Purification Methods. For apartment-specific tips, see our Urban Survival Guide.