Propane Usage Calculator
Calculate propane consumption from appliance BTU and daily usage hours.
Returns gallons per day, week, and month with cost estimate for grills and heaters.
Propane tank usage and cost tracking helps homeowners budget heating expenses, avoid unexpected runouts, and compare propane to natural gas or electricity alternatives. Propane consumption depends on appliance BTU ratings, usage hours, and local propane prices.
Formulas: Propane Used (gallons/hr) = Appliance BTU/hr ÷ 91,452 BTU/gallon Days Until Empty = (Tank Capacity in gallons × Fill % remaining) ÷ Daily Usage (gallons) Monthly Cost = Monthly Usage (gallons) × Price per Gallon Annual Cost = Annual Usage × Average Price per Gallon
Propane energy content:
- 1 gallon of liquid propane = 91,452 BTU (British Thermal Units)
- 1 lb of propane = 21,548 BTU
- 1 gallon propane weighs approximately 4.24 lbs
Common propane appliance BTU ratings:
| Appliance | BTU/hr | Gallons/hr |
|---|---|---|
| Propane furnace (100k BTU) | 100,000 | 1.09 |
| Water heater (40k BTU) | 40,000 | 0.44 |
| Gas range (5 burners, all on) | 65,000 | 0.71 |
| Fireplace log set | 30,000–40,000 | 0.33–0.44 |
| Generator (20kW) | 200,000 | 2.19 |
| Clothes dryer | 20,000 | 0.22 |
Worked example — home heating: 500-gallon tank at 70% full = 350 gallons available Home uses a 100,000 BTU furnace running 6 hours/day in winter.
Daily propane use = 1.09 gal/hr × 6 hr = 6.54 gallons/day Days until empty = 350 ÷ 6.54 = 53.5 days
Monthly heating cost (October–March, 6 months): Monthly gallons = 6.54 × 30 = 196.2 gallons/month At $2.50/gallon: 196.2 × $2.50 = $490.50/month 6-month heating season total: $2,943
Price comparison (per 100,000 BTU of heat):
- Propane at $2.50/gal: 100,000 ÷ 91,452 × $2.50 = $2.73
- Natural gas at $1.50/therm: 100,000 ÷ 100,000 × $1.50 = $1.50
- Electricity at $0.14/kWh (resistance heat): 100,000 ÷ 3,412 × $0.14 = $4.10
- Electric heat pump (3× efficient): $4.10 ÷ 3 = $1.37
Tip: Order a fill when the tank is at 30–25% — avoid emergency delivery surcharges and guarantee supply during peak winter demand.