Propane Calculator
Calculate propane tank fill cost, BTU capacity, monthly usage by appliance, and annual heating cost. Covers 20 lb BBQ tanks up to 1,000 gallon residential tanks.
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Tank Capacity (gallons)
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BTU Capacity —
Full Fill Cost —
Est. Burn Time (60k BTU/hr) —
Extended More scenarios, charts & detailed breakdown ▾
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Gallons to Fill (to 80%)
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Fill Cost —
Est. Days Remaining (avg home) —
Professional Full parameters & maximum detail ▾
BTU/hr
hrs
BTU/hr
hrs
BTU/hr
hrs
BTU/hr
hrs
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Annual Propane Usage
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Annual Fuel Cost —
Tank Rental (if applicable) —
Total Annual Cost —
Budget Plan (12 equal payments) —
Largest Consumer —
How to Use This Calculator
- Select your tank size (20 lb BBQ tanks through 1,000 gallon residential tanks).
- Enter the current propane price per gallon in your area.
- See BTU capacity, estimated burn time, and fill cost instantly.
- Use Tank Fill tab to calculate how much you need to fill to 80% from your current level.
- Use Monthly Usage tab to enter your appliances and get monthly consumption and cost.
- Use the Professional tab for all appliances, annual cost, and budget plan calculation.
Formula
Gallons = Tank lbs × 0.236 (for lb tanks) or direct gallons
BTU Capacity = Gallons × 91,502 BTU/gal
Daily Gallons = Σ(Appliance BTU/hr × Hours/day) ÷ 91,502
Example
500 gallon tank at $2.80/gal: Fill cost (to 80%) = 500 × 0.80 × $2.80 = $1,120. An 80,000 BTU furnace running 6 hrs/day: 80,000 × 6 ÷ 91,502 = 5.25 gal/day, $14.70/day.
Frequently Asked Questions
- A 100 lb propane tank holds approximately 23.6 gallons. Propane weighs about 4.24 lbs per gallon at 60°F. Tanks are never filled past 80% capacity for safety, so a 100 lb tank holds a max of ~18.9 usable gallons.
- An 80,000 BTU furnace burns about 0.87 gallons per hour (80,000 ÷ 91,502 BTU/gal). Running 6 hours/day uses ~5.2 gallons/day or ~156 gallons/month during heating season.
- Propane contains 91,502 BTU per gallon (liquid). This is why propane is a dense, efficient fuel — compare to natural gas at 1,020 BTU per cubic foot, or electricity at 3,412 BTU per kWh.
- Refill when the gauge reads 20–30%. Never wait until empty — you could run out during bad weather, and propane companies charge extra for emergency delivery. Most suppliers offer automatic delivery when usage patterns suggest you're running low.
- Budget plans spread your annual cost into 12 equal monthly payments. This helps with cash flow and protects against winter price spikes. Most companies offer this service. Calculate your estimated annual usage first to compare with the plan amount offered.