Two sums, both in litres and cans. Water is sized against a published humanitarian standard. Fuel is sized by distance or by running hours, depending on what you actually operate.
Every default above is either a published standard, named where it is used, or a planning margin you can change. Nothing here is a quotation. Carton and container figures appear only for products where the factory has given us real dimensions; everything else says so.
The water rates in this tool are the headline figures from the Sphere Handbook's minimum standards in water supply, sanitation and hygiene promotion: 15 litres per person per day for drinking, cooking and hygiene, 7.5 litres in the acute phase for a short time, and up to 50 litres in urban or protracted contexts. Survival intake alone is 2.5–3 litres.
A truck burns fuel over distance. A boat, a generator and a tractor burn it over time, because the engine runs whether or not you are covering ground. Sizing a vessel's fuel from a distance figure is a common and expensive mistake, so the tool changes its inputs to match what you operate rather than asking everyone for kilometres.
Marine defaults to a 50% reserve, which is the one-third rule: a third out, a third back, a third untouched.
The calculator gives you a quantity. We will give you a specification sheet, a carton and container breakdown, and a price at your volume.