Propane Usage Calculator
Estimate how long a propane tank lasts for your grill, heater, or generator, and what each hour of use costs.
Processed locally in your browser — nothing is uploaded.
Propane Usage Calculator
On the data plate or in the manual — this is the max-output draw.
Burners rarely run wide open; 50–75% is common.
A full 20 lb tank holds about 430,000 BTU.
Results
- Burn time per tank
- 19.1 hours
Estimates assume the tank is filled to capacity (exchanges are often only ~80% full) and a steady draw at the chosen usage level.
About Propane Usage Calculator
A 20 lb propane tank holds roughly 430,000 BTU. Divide that by your appliance's draw — its BTU/hr rating times how hard you actually run it — and you get burn hours per tank; add your refill price for cost per hour. Presets cover typical grills (30k BTU/hr), patio heaters (40k), generators (90k), and more, and every number is editable.
Common uses
- Check whether the tank will last through a cookout or party
- Budget patio heater running costs for a season
- Plan generator fuel for an outage
Example
Input
30,000 BTU/hr grill at 75%, 20 lb tank, $22 refill
Output
19.1 hours per tank · $1.15 per hour
Limitations
- Appliance ratings are maximum output; real draw depends on settings and weather.
- Tank exchanges are often filled to ~80% of capacity, and BTU-per-tank figures are nominal — treat results as planning estimates.
Frequently asked questions
How long does a 20 lb propane tank last on a grill?
Roughly 18–20 hours of typical grilling. A full 20 lb tank holds about 430,000 BTU; a 30,000 BTU/hr grill run at 75% of full blast draws 22,500 BTU/hr, and 430,000 ÷ 22,500 ≈ 19 hours.
How many BTU are in a 20 lb propane tank?
About 430,000 BTU when full — propane delivers roughly 21,500 BTU per pound. A 30 lb tank holds about 645,000 BTU and a 100 lb tank about 2,150,000, scaling linearly with weight.
Why does my tank run out faster than the calculator predicts?
Two usual reasons: appliance BTU ratings are maximums, so cold weather or high settings push your real draw above the usage level you picked, and exchange tanks are often filled to only about 80% of capacity. Adjust the usage percentage and tank BTU to match reality.
Does this calculator send my inputs to a server?
No. Burn-time and cost math happens locally in your browser, and none of the appliance details or prices you enter are transmitted or saved.
What does the usage level percentage mean?
It's the fraction of the appliance's maximum BTU rating you actually run — the duty cycle. Burners rarely run wide open, so 50–75% is typical for grilling; a generator under heavy load or a heater on high in cold wind runs closer to 100%.