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How long will my water last?
Already have water stored? See how many days it covers for your household.
How it is worked out
Days = water you have ÷ (people × one gallon a day). One gallon per person per day is the amount Ready.gov recommends for drinking and basic hygiene; in very hot weather it doubles. Ready.gov recommends having water for at least several days.
Making water go further
- Ready.gov advises that you never ration drinking water unless the authorities tell you to. Drink what you need and look for more.
- Save drinking water for drinking: wash with less, and use wet wipes and hand sanitiser.
- Water from an unknown source must be boiled or disinfected first.
Need more? Plan it with the water storage calculator.
For planning and general information. In an emergency, follow the instructions of your local authorities and call your emergency number (911, 112, 999 or 000).
More water tools
Emergency water storage calculatorHow much water to storeWater purification with bleachDrops of bleach per litre or gallonHow long to boil water to make it safeBoiling time by elevationRainwater collection calculatorWater from rain on a roof
Source: Ready.gov, Water (US Federal Emergency Management Agency).