Oil and propane tank calculator
Read your tank, enter the reading, and see how many gallons are left. For heating oil that is a dip stick or float gauge in inches; for propane it is the percent on the gauge. Add a few dated readings and it also estimates when the tank runs low at the rate you have been using it.
How the numbers are worked out
- The float gauge on a home propane tank shows percent of the tank's full water capacity. Gallons are capacity × percent ÷ 100, so 50% on a 500 gal tank is 250 gal. Dead River's gauge table lists the same figures for 120, 250, 325, 500 and 1,000 gal tanks.
- Tanks are filled to about 80% so the liquid has room to expand on warm days (MFA Oil). The last column is what a fill to that line would bring.
- The run-out estimate turns each reading into gallons, adds back deliveries made between readings, and divides what was used by the days between the first and last reading.
- A dial gauge is read by eye, so a single reading can be a few percent off. Readings further apart give a steadier rate.
Guides
- 275 gallon oil tank chart: standing and lying down, every inch, and how to dip.
- How long will heating oil last: the run-out math with a worked example.
- 1200 litre oil tank chart: bunded plastic tanks in the UK and Ireland, by depth in cm.
- 500 gallon propane tank chart: gauge percent to gallons, and how long a tank lasts.
- Propane tank percentage chart: gauge percent to gallons for 120 to 1,000 gal tanks, side by side.
- How much propane does a furnace use per day: gallons per hour and per day from your furnace's rating and the weather.
- Heating fuel cost comparison: oil, propane, gas, electric, heat pump, pellets and wood per million Btu, at your prices.
- Heat pump vs oil heating cost: the electricity price where a heat pump matches oil, by COP and oil price.