Convert Gallon (US) (gal (US)) to Acre-Foot (US Survey) (ac*ft (US)) instantly.
About these units
Gallon (US) (gal (US))
The US gallon is defined as exactly 231 cubic inches, or 3.785411784 liters. It is widely used in American commerce for gasoline, milk, water, and other household liquids. Its historical roots lie in old English wine and ale gallons, whose varying definitions ultimately led to divergent US and UK systems. Today, the US gallon remains deeply embedded in American culture, especially in automotive contexts—fuel economy ratings such as "miles per gallon" (MPG) illustrate its everyday relevance. Despite the global shift toward metric volume units, the US gallon persists due to familiarity and regulatory inertia. It remains an iconic unit, symbolizing uniquely American measurement traditions.
Acre-Foot (US Survey) (ac*ft (US))
The US survey acre-foot differs extremely slightly from the international acre-foot due to the slight difference between the survey foot and the international foot. While the distinction is negligible in most contexts, it is important in surveying, legal water rights, and long-term hydrological accounting, especially in regions where large historical datasets were recorded using US survey measures. This variant highlights how even subtle unit differences can have major implications when dealing with huge volumes over long timescales, such as state water budgets and inter-state compacts.