WATTREADY Generator tools

How long will your generator run — and what will it cost?

Enter your generator's size, fuel type, and tank capacity to see runtime and fuel cost at any load level, plus a full breakdown across common load levels.

Your generator

Find this on the generator's data plate or spec sheet — the "rated" or "running" watt figure, not the surge/starting figure.
Enter a rated wattage greater than 0.
For propane tanks sized in pounds: a standard 20 lb cylinder holds about 4.7 gallons of liquid propane.
Enter a tank size greater than 0.
Enter a price of 0 or more.

Load level

50%
Most people run essentials at 40–60% of rated capacity, not 100%. Higher load burns fuel faster but runtime-per-dollar is usually similar.

Runtime and cost by load level

LoadFuel useRuntime on full tankCost per hour
This is an estimate, not a spec. Fuel consumption varies by generator model, engine efficiency, altitude, and temperature — the figures here use typical published consumption rates for each fuel type and scale them by your rated wattage and load. For an exact number, check your generator's own fuel consumption chart, usually printed on the unit or in the owner's manual.

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