Generator Runtime & Fuel Calculator
Estimate how long a generator will run on a tank or cylinder of fuel, and what that fuel costs per hour. Enter the rated output, the load you're drawing, and your fuel: the calculator works out the burn rate, runtime, and hourly and daily fuel cost.
Estimated runtime on this fuel
11.4 hours
- Fuel use
- 0.70 gal/hr
- Fuel cost / hour
- $2.45
- Fuel cost over 24h
- $59
Fuel use rises with load: a generator at half load burns far less than at full load. This is a planning estimate; check the unit's spec sheet for its fuel-consumption curve. A natural-gas standby unit runs indefinitely on the utility supply. Never run a generator indoors (carbon monoxide risk), and refuel only when the engine is cool.
Inverter generators by size
Inverter generators throttle down at light load, which is where most of their runtime advantage comes from. Run any generator outdoors, well away from doors and windows.
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Mid-size inverter (3,000–6,000 W running)
WEN DF680iX
Best for: Furnace blower, fridge and sump pump in an outage, or an RV with one air conditioner
Small inverter (under 3,000 W running)
Honda EU2200i (EU2200ITAN)
Best for: A refrigerator, internet and electronics through an outage, or quiet power at a campsite
Frequently asked questions
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Runtime on a fuel generator depends on the tank. On a battery power station it depends on capacity, and the figures are exact rather than estimated. See the portable power station picks.
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Sources & standards
This tool's methodology and data follow US standards and authoritative public datasets: