Propane: 91,502 BTU per Gallon  How Many BTUs are in a Gallon of Propane  BTU Value of Propane
The BTU value of propane is the energy content of propane, as measured in BTUs. Propane BTU per gallon: BTU value of one gallon of propane 91,502 BTU (British Thermal Units). So, 91,502 BTU is how many BTUs in a gallon of propane (BTU value of propane).
Propane Conversions: Pounds, Gallons, BTU, Therms & ft³ including propane BTU per gallon, propane BTU per cubic foot, propane therms to gallons and propane gallons to pounds conversion. There are 91,502 BTU in a gallon of propane.
Many of the other questions ask about the various Propane conversion values in US gallons, pounds, BTUs, therms and cubic feet.
The easiest way to answer most of them is with a Propane conversion chart or table…
LPG BTU per Gallon
LPG BTU per Gallon is 91,502 BTU (British Thermal Units). So, 91,502 BTU is how many BTUs in a gallon of LPG (BTU value of LPG).
Gallons to Pounds Propane Conversion  Propane Gallons to Pounds Conversion
1 gallon of propane weighs 4.23 pounds. So, a full 20 lb cylinder should contain 4.73 gallons of propane.
For gallons to pounds propane conversion (propane gallons to pounds conversion), 1 gallon of liquid propane = 4.23 pounds. A full 20 pound propane tank contains 4.73 gallons of propane. One pound of propane = 0.236 gallons (30.2 Ounces) of liquid propane.
A 20lb (4.73 gallon) propane tank has 432,804 BTU, based on propane BTU per gallon of 91,502 BTU @ 60ºF.
Propane Weight to Volume
For propane weight to volume, 1lb of propane @ 60ºF is 0.24 US gallons, for liquid propane. 1 lb = 8.59ft³ for gaseous propane.
For metric propane weight to volume, 1 kg propane is 1.96 litres of propane, for liquid propane. 1kg = 0.546m³ for gaseous propane.
Propane BTU per Litre = 23,700 BTU per Liter  Propane BTU Conversion for Volume
Propane BTU per liter = 23,700 BTU per litre of propane. In propane BTU per litre, which is a propane BTU conversion for volume, it combines an old imperial energy measurement  BTU  with a metric volume measurement  litre.
Propane BTU per litre = 23,700 BTU per litre of propane. 1MJ equals 948BTU, so to get an equivalent number of BTU, just multiply the MJ rating by 948.
1L = 25 MJ. So, to calculate propane BTU per liter: 25 MJ x 948 = 23,700 BTU
As a related value, propane BTU per kg  LPG BTU per kg: 1kg = 46,452 BTU
Combining metric and imperial measures is not typical but it can be easily calculated, as shown.
Propane BTU Conversion  BTU Value of Propane  Propane to BTU Conversion
In the propane BTU per gallon conversion, the BTU value of propane is 91,502 BTU in 1 gallon of propane gas. If you need to convert BTU to gallons of propane, you simply divide the entire BTU requirement by 91,502 BTU.
For propane therms to gallons, there are 1.1 (propane) therms per gallon. Propane BTU per liter = 23,700 BTU per liter.
Propane BTU (British Thermal Units) is a measurment unit for energy contained in the propane.
The following propane BTU conversion chart shows the common conversions including propane BTU per gallon, propane BTU per cubic foot (ft^{3}), propane BTU per pound and more...
BTU Value of Propane
You can see how propane BTU value is better than natural gas when you buy a cooktop. Cooktops usually come with two sets of gas jets. The jets for propane have a much smaller hole and use less gas. That’s because propane contains more heat energy, with 2572 Btu/ft³ vs natural gas at 1011 Btu/ft³ (93.2MJ/m³ vs 38.7MJ/m³).
BTU Content  LPG Heating Value BTU
The BTU value of propane is the enrgy content of propane, as measured in BTUs. The following chart shows the BTU value of propane for various measurement units:
Quantity of Propane Fuel  BTUs 
1 Gallon of propane  91,502 BTU 
1 Cubic Foot (ft^{3}) of propane  2,488 BTU 
1 Pound of propane  21,591 BTU 
1 Litre (1 Liter) of propane  23,700 BTU 
1 Cubic Meter (m^{3}) of propane  87,863 BTU 
1 MJ of propane  948 BTU 
1 Therm of propane  100,067 BTU 
All at 60ºF. Some BTU values are rounded
Copyright © 20102019. Elgas Ltd.

Propane Conversion Values
The following are some of the most common propane conversion values including propane BTU per gallon, propane BTU per cubic foot, propane therms to gallons and propane gallons to pounds conversion:
♦ BTU per Gallon of Propane: 1 Gallon = 91,502 BTU @ 60ºF
♦ BTU per Cubic Foot (ft^{3}) of Propane: 1 cubic foot = 2,488 BTU @ 60ºF
♦ Therms to Gallons of Propane: 0.915 therms = 1 Gallon
♦ Gallons to Pounds Conversion of Propane: 1 Gallon = 4.23 Pounds
♦ Pounds to Gallons of Propane: 1 Pound = 0.236 Gallons (30.2 Ounces)
♦ Gallons to Cubic Feet (ft^{3}) of Propane: 1 Gallon = 36.4 ft^{3} (Vapour/Gas)
♦ Cubic Feet (ft^{3}) to BTU of Propane: 1 cubic foot = 2,488 BTU @ 60ºF
♦ Convert BTU to Gallons of Propane: 91,502 BTU = 1 Gallon
♦ BTU per pound of Propane: 1 Pound = 21,591 BTU @ 60ºF
♦ BTU per Litre (Liter) of Propane: 1 Litre = 23,700 BTU
♦ BTU per kg of LPG  BTU per kg of Propane: 1kg = 46,452 BTU
♦ Gallons to Therms of Propane: 1 Gallon = 0.915 therms
Note that all of the above are expressed in US Gallons.
Propane Conversion Charts  Propane BTU per Gallon  How Many BTUs are in a Gallon of Propane
The charts below cover most of the common units of measure and gas bottlecylinder sizes for the USA including Propane BTU per Gallon (How Many BTUs are in a Gallon of Propane). You can convert:

Propane BTU per Gallon

Propane BTU per Cubic Foot (ft^{3})

Propane Therms to Gallons

Propane Gallons to Pounds Conversion

Propane Pounds to BTU or vice versa

And all other combinations
Imperial Gallons
Some countries use Imperial Gallons, which are about 20% larger than US Gallons.
To be exact, 1 Imperial Gallon ≈ 1.200950 US gallons
Note that most of these countries have converted to litres, in the metric system.
Gallons, Pounds, BTUs, Therms & Cubic Feet (ft^{3})
Units of Measure

Equivalent Units

1 US Gallon

4.23 Pounds
(4 Pounds 3.7 Ounces)

1 Pound

0.236 Gallons
(30.2 Ounces)

1 US Gallon

91,502 BTU @ 60ºF

1 US Gallon

0.915 therm

1 cubic foot

2,488 BTU @ 60ºF

1 US Gallon

36.4 ft^{3 }Gas

1 Litre

23,700 BTU

Note: Some numbers have been rounded.
Propane BTU Conversion  Propane BTU per Gallon
Multiply the number of gallons of propane by 91,502, which is the number of BTUs in a gallon. For example, 10 gallons of propane would produce 915,020 BTUs of heat energy.
Propane BTU conversion is the most common conversion measures of propane energy content including propane BTU per gallon, propane BTU per cubic foot, propane therms to gallons and propane gallons to pounds conversion.
BTU is the acronym for British Thermal Unit, a unit of energy.
Propane BTU conversion is needed as gas appliances are rated in Propane BTU, based on the required energy input.
Propane BTU conversion is also used by gas companies to determine total gas load on a system when everything is running on maximum.
One BTU is the amount of heat required to raise the temperature of 1lb of water by 1°F, at sea level.
The relative efficiency of the propane BTU conversion input into the gas appliance determines the heat output.
More propane BTU conversion energy content facts:
Propane BTU per Gallon  How Many BTUs are in a Gallon of Propane  91,502 BTU
In the propane BTU per gallon conversion, there are 91,502 BTU in 1 gallon of propane gas. "How many BTUs are in a gallon of propane?" is a very common question. It helps to calculate the gas consumption of an appliance, based on the BTU rating of the appliance.
In the propane BTU per gallon conversion, to convert BTU to gallons of propane just divide BTU by 91,502.
Propane BTU per Gallon: is 91,502 BTU (Propane BTU per galllon).
Propane BTU per 100 gallon propane gas tank is 9,150,200 BTU.
Propane BTU per Gallon of a 20lb tank: 4.73 gallon (20lb) propane tank is 432,804 BTU.
So, if you divide 91,502 by the BTU rating of the appliance, you can calculate how much propane will be used by the appliance per hour.
You can also calculate how many hours a certain propane gas bottle size will last by dividing the BTU of the contents by the BTU rating of the appliance.
The following are the values for BTU in 1 gallon of propane gas and per ft^{3} of propane gas, as well as the values in MJ, litres and watts:

Propane BTU per Gallon: 1 Gallon = 91,502 BTU @ 60ºF

Propane BTU per Cubic Foot (ft^{3}): 1 cubic foot = 2,488 BTU @ 60ºF

Propane Therms to Gallons: 0.915 therms = 1 Gallon

Propane Gallons to Pounds Conversion: 1 Gallon = 4.23 Pound

Propane BTU per MJ: 1MJ = 948 BTU

Propane BTU per Watt: 1 watt = 3.41214 BTU/hr

BTU per Litre of Propane Liquid: 1 Litre = 23,700 BTU
Convert BTU to Gallons of Propane
Convert BTU to gallons of propane by dividing the BTU by 91,502. You simply divide the entire BTU requirement by 91,502 BTU.
Conversely, multiply the number of gallons of propane by 91,502, which is the number of BTUs in a gallon. For example, 10 gallons of propane would produce 915,020 BTUs of heat energy.
So, if you know the BTU/hr consumption of an appliance and multiply by how many hours you intend to run it, you arrive at the total propane BTU requirement.
Then you divide the total propane BTU requirement by 91,502 to determine how many gallons of propane will be required.
As an example, you have a gas heater with a 23,700 BTU (25MJ) per hour consumption and you want to run it for 8 hours.
23,700 x 8 = 189,600 BTU requirement
189,600 ÷ 91,502 = 2.072 gallons of propane required
Propane to Natural Gas BTU Conversion  Convert Gallons of Propane to Cubic Feet of Natural Gas
To convert gallons of propane to cubic feet of natural gas remember 1 gallon of propane contains 91,502 BTU whilst one cubic foot of natural gas equals 2,488 BTU. So, convert gallons of propane to cubic feet of natural gas, simply divide 91,502 by 2,488, which equals 36.78 cubic feet of natural gas. So, 1 gallon of propane equals 36.78 cubic feet of natural gas.
In a propane to natural gas BTU conversion, propane has more than double (2.42 times) the energy of natural gas, per cubic foot.
Propane BTU per cubic foot: 1 Cubic Foot (ft^{3}) = 2,488 BTU
Natural Gas BTU per cubic foot: 1 Cubic Foot (ft^{3}) = 1,030 BTU
1 Gallon = 91,502 BTU @ 60ºF
Propane to Natural Gas BTU Conversion
In a propane to natural gas BTU conversion, propane has more than double (2.42 times) the energy of natural gas, per cubic foot.
Propane BTU per cubic foot: 1 Cubic Foot (ft^{3}) = 2,488 BTU
Natural Gas BTU per cubic foot: 1 Cubic Foot (ft^{3}) = 1,030 BTU
How Many Therms per Gallon of Propane: Propane Therms per Gallon
Multiply the number of gallons of propane by 0.915 to get the number of therms. This is because one therm equals 100,067 BTUs. For propane therms to gallons, there are 1.1 (propane) therms per gallon. This is for US gallons of propane.

Propane Therms per Gallon: 1 Therm = 1.1 US gallons of propane

Propane US Gallons per Therm: 0.915 gallons of propane = 1 therm

Propane BTU per Therm: 1 therm = 100,067 BTU
So, if you want to convert propane therms to gallons, it is 1 (propane) therm per 0.915 gallon.
CFH to BTU Propane  Propane BTU Conversion for Gaseous Volume  Propane BTU per Cubic Foot
Propane BTU per cubic foot: 1 cubic foot = 2,488 BTU @ 60ºF so, one CFH equals 2,488 BTU per hour: 1CFH = 2,488BTU/hr.
Propane contains 2,488 BTU whilst 1 cubic foot of natural gas contains 1011 BTU. Therefore, the energy content of propane is more than double that of natural gas, when measured by gaseous volume.
In the propane BTU conversion for gaseous propane, the CFH to BTU propane is based on the flow rate of CFH being Cubic Foot per Hour, so 1 CFH = 2,488 BTU per hour of propane.
Remember that Propane BTU per cubic foot (ft^{3}): 1 cubic foot of propane = 2,488 BTU @ 60ºF
So, one CFH equals 2,488 BTU per hour: 1CFH = 2,488BTU/hr
Example of a CFH to BTU propane calculation:
If the flow rate is 20 cubic feet per hour, the total BTU of heat produced per hour would be 2,488 BTU/cubic foot x 20 cubic feet/hour = 49,760 BTU per hour.
Propane BottleCylinder Sizes  Domestic LPG Cylinder Dimensions
Propane cylinderbottle sizes incorporate domestic LPG cylinder dimensions including the 100lb propane cylinder size, 200lb propane bottle size and 420lb propane cylinder sizes.
The various propane bottle sizes exist because different people used different amounts of gas and the propane cylinder sizes are selected accordingly.
Domestic propane bottlecylinder sizes are the same for LPG bottle sizes and propane bottle sizes, as they are the same gases. Propane is also called LPG, as is butane.
Propane Cylinder Dimensions  Sizes
Not surprisingly, when propane cylinder sizes are discussed, it is in USA measurements.
This is because the USA uses the term 'Propane' in lieu of 'LPG'.
So, where LPG cylinder sizes are conveyed in kilograms, propane cylinder sizes are expressed in pounds.
Therefore, in the table below, the propane cylinder sizes are in pounds...
For Australian LPG gas bottles & cylinders:
See metric conversions of LPG in kg, Litres, MJ, kWh, BTU & m³
How Many Gallons in a 20 Pound Propane Tank?
A 'full' 20 pound propane tank would contain 4.73 gallons of propane.
A 20lb (4.73 gallon) propane tank has 432,804 BTU, based on propane BTU per gallon of 91,502 BTU @ 60ºF.
Note that in some US tank exchange programs, the fill is something less than 20 pounds and is labelled accordingly.
The image above is a typical 20 pound (9kg) propane tank.
How Many Gallons are in a 100 lb Propane Tank  23.64 Gallons in a 100 lb Propane Tank
There are 23.64 gallons in a 100 lb propane tank. Propane is sold by weight and 100 lb propane tanks are typically filled on digital scales. A 100 lb propane tank weighs about 71 lb when empty and 171 lb when full. 100 lb is the net weight of the gas contents.
A 100lb (23.64 gallon) propane tank has 2,095,396 BTU, based on propane BTU per gallon of 91,502 BTU @ 60ºF.
A 100 pound tank is roughly the same size as a 45kg gas bottle.
They are small enough to be exchanged or tanker filled.
The image to the right is of a typical 100 pound propane tank.
100 lb Propane Tank Dimensions
100 lb propane tank dimensions for width and height are approximately 14¾ in x 47½ in (375mm x 1206mm). 100 lb propane tank dimension for tare weight is 71 lb (32.2kg) and capacity is 25 gal (94.6L). This varies based on the tank manufacturer.
100 lb Propane Tank Dimensions Chart
100 lb Propane Tank Dimensions  

Height  47½ in  1206mm 
Diameter  14¾ in  375mm 
Tare Weight  71 lb  32.2kg 
Capacity  25 gal  94.6L 
Copyright © 2019 Elgas Ltd. 
Background Information
Propane Specific Gravity  Density
Unlike water, 1 pint of propane does not weigh ≈ 1lb. It actually weighs 0.51lbs.
This is because the density or specific gravity of propane is only about half that of water.
Converting from weight to volume, 1lb of propane @ 60ºF has a volume of 0.24 US gallons.
Conversely, 1 US gallon of propane @ 60ºF only weighs 4.23lbs, instead of the 8.34lbs it would weigh if it was water.
Important Note:
All volumes are quoted in US gallons, as opposed to imperial gallons.
Imperial gallons are 20% larger.
Propane Liquid to Gas Volume Expansion
Propane expands about 270 times in volume when it goes from liquid to gas.
So, 1 US gallon of liquid propane equals 36.4 ft^{3 }of gaseous propane
Gas Bottle Tare Weight
Tare weight is the empty weight of the gas bottlecylinder.
Along with the gas bottle dimensions, they can vary greatly by manufacturer and date of manufacture.
For example, older bottles tend to be heavier than more recent versions.
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The information in this article is derived from various sources and is believed to be correct at the time of publication. However, the information may not be error free and may not be applicable in all circumstances.