Propane runtime calculator for generators

If you know roughly how many gallons of propane you have and how quickly your generator uses it, you can get a simple runtime estimate.

This calculator uses a basic gallons-per-hour approach to help plan fuel for outages or RV trips.

Propane runtime calculator

Estimate generator runtime on propane based on tank size and an approximate fuel consumption rate.

Propane available (gallons)

For common cylinders: 20 lb ≈ 4.7 gal, 30 lb ≈ 7 gal, 40 lb ≈ 9.4 gal.

Fuel consumption (gallons per hour)

Many mid-size portables burn somewhere around 0.4–0.8 gal/hour at moderate load.

For more planning tools, you can also use the other calculators and guides on the GeneratorCalc home page.