Generator Fuel Consumption Calculator

Estimate run time and gas/diesel fuel costs for portable emergency generators and whole-house standby units.

Calculator Parameters

Distance unit
Fuel economy unit
$per US gallon

This is an estimated default price. Automatic price detection only applies to visitors in the United States. Everyone else can select their own currency and enter a local price below for an accurate result.

Currency

Enter total travelers to split gas cost fairly.

Trip type
Timeframe

Your Calculation Results

High Consumption (> 8.5 L/100km)
Total Fuel Needed (for this trip)
5.18 US gallons
(19.6 liters total)
Total Fuel Cost (for this trip)
$7.77
Cost breakdown per distance unit
$0.125 per mile • $0.078 per km
Total Distance (for this trip)
100.0 kilometers

Fuel economy in every unit

L/100km
19.6
MPG US
12.0
MPG UK
14.4
km/L
5.1

Generator Fuel Burn Rates & Runtime Planning

Generator fuel consumption depends directly on electrical load demand (percentage of rated output). Running at 100% capacity consumes nearly double the fuel compared to operating at 50% load.

Generator CapacityFuel Type50% Load Burn Rate24-Hour Fuel Needed
2,000 W InverterGasoline0.15 GPH3.6 Gallons
5,500 W PortableGasoline0.75 GPH18.0 Gallons
10,000 W IndustrialDiesel0.85 GPH20.4 Gallons
22,000 W StandbyPropane (LPG)2.10 GPH50.4 Gallons

Related Calculators & Tools

Explore our full suite of specialized calculators for specific vehicles, equipment, and fuel conversions:

Fuel Consumption CalculatorCore calculator for trip fuel, MPG, L/100km & passenger cost splitMPG CalculatorCalculate Miles Per Gallon & US/UK gallon conversionsL/100km CalculatorEuropean & Canadian metric fuel consumption calculatorKM/L CalculatorKilometers per liter fuel economy calculationCost Per MileExact gas cost per mile or per kilometer for commuters & ridesharesMonthly Fuel CostEstimate monthly gas expenses for daily commutes & annual budgetsFuel Unit ConverterConvert between MPG, L/100km & KM/L instantlyBoat Fuel CalculatorOutboard & marine engine GPH fuel consumptionTruck Fuel CalculatorCommercial semi-truck & pickup diesel trip costsTowing CalculatorFuel penalty when towing trailers, campers, or RVsIdle Fuel CalculatorCalculate fuel and money wasted while idlingEV vs Gas ComparatorCompare electric vehicle charging vs gasoline running costs
Browse Vehicle Database →Browse Highway Driving Routes →Regional Gas Prices →Vehicle Fuel Comparison →

Frequently asked questions

A typical 5,000 to 6,500 Watt portable gas generator consumes approx 0.75 gallons (2.8 liters) of fuel per hour at 50% electrical load.

A 22 kW home standby generator burns approx 2.1 gallons of propane per hour or 225 cubic feet of natural gas per hour at 50% electrical load.

Calculate continuous run hours per day (e.g., 16 hours/day) × GPH consumption rate (e.g., 0.75 GPH) × 7 days. For a 5 kW generator, 16 hrs × 0.75 GPH × 7 = 84 gallons of gasoline.