United States household resilience
FEMA Ready guidance uses one gallon of water per person per day for at least three days, for drinking and sanitation, and recommends a several-day supply of non-perishable food.
Local hazards and official instructions vary greatly across states and territories. Use local emergency management and utility guidance during an incident.
Use the global resilience check
The main calculator lets you combine electricity, gas/fuel, mains water, food-supply and communications disruptions, then compares your stored water, shelf-stable food and backup phone energy with the selected planning horizon.
Open the resilience calculator
What limiting resilience does — and does not — mean
The headline day figure identifies the earliest modelled resource limit in the selected scenario. The secondary 0–100 scenario score summarises broader coverage. Neither is a forecast of how long it is safe to remain at home, and neither replaces emergency services, public-health guidance, evacuation orders or professional advice.
Use the same plan in your preferred units
The global calculator keeps its country guidance pack separate from display units. You can use the automatic country default or switch water quantities between litres, US gallons and UK imperial gallons without changing the underlying planning target.
What the US country pack changes
The US country pack defaults to US customary gallons and uses the Ready.gov one-gallon-per-person-per-day baseline. Users can still switch the display to litres or UK gallons without changing that underlying quantity.
Preparedness advice can also vary by state, territory and hazard. The country page therefore supplies a national baseline while the live scenario remains deliberately generic about local evacuation, wildfire, hurricane, earthquake or winter-storm instructions.
What stays the same globally
The dependency engine, limiting-resilience calculation, device-load planner, food-usability logic, copy controls and printable plan use the same method in every supported country. Localisation changes the guidance source, water baseline, emergency references and default display units rather than creating a different product.