Why it matters
Understand
the numbers.
Every figure above has a reason behind it. This is what each one protects against.
Water decides first
At the one-gallon survival minimum, a family of four drinks through a 55-gallon barrel in under two weeks. Water is the resource most people overestimate.
Power runs everything else
An electric well pump, a freezer and a furnace blower all stop with the grid. A generator lasts only as long as its fuel, which is why the tool counts gallons, not watts.
Medicine has no substitute
Food can be stretched and water rationed. A daily prescription cannot. For many households it is the first thing to run out.
Method
How we
calculate.
Planning figures, not guarantees. Final systems are engineered for the site, the climate and the household.
Water is gallons stored divided by people at one gallon per person per day, the federal survival minimum. A well with solar or a hand pump counts as unlimited. An electric pump only adds days while backup power lasts.
Food is the number of days you enter. Power counts a generator at about eight gallons of fuel a day of running; solar with batteries counts as independent.
Heat only limits households with freezing winters. Medicine uses the supply band you choose. The headline is the lowest of water, food, heat and medicine. Power is shown on its own because a household can live without it for a while, but not comfortably.
The vertical line on each bar marks 180 days, the Styrkholm standard. Reported Pentagon planning puts 90 days as the floor for military bases.
Questions
Common
questions.
What counts as a day of independence?
One day your entire household can live at home with no deliveries, no utilities and no outside services: no grid power, no municipal water, no stores and no pharmacy.
Why 180 days and not 90?
Ninety days is the planning floor reported for U.S. military bases. A private household cannot be resupplied the way a base can, and a disruption that begins in the fall must be carried through an entire winter. One hundred eighty days covers that.
Is my answer saved?
No. Everything runs in your browser. Nothing is sent unless you choose to submit the consultation form, which then includes a one-line summary of your result.
Private Consultation
Bring us
your numbers.
Send your results with a consultation request and we will walk through them with you, privately and without obligation.
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