Propane Usage Calculator

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:

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

The calculator carries the full 1.0934 gal/hr rather than the rounded 1.09, so it reports 6.56 gallons a day and 53.3 days. The difference is rounding, not disagreement.

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

Order a fill at 30%, not at 10%. Waiting costs money and can cost you heat. Emergency winter delivery carries a surcharge, suppliers get booked out during a cold snap exactly when everyone else has also left it late, and a tank that actually runs dry has to be leak-tested and every pilot relit by a technician before it can be refilled. Thirty percent buys you the slack to schedule a routine delivery instead.