Unit Conversion Factors

The conversion factors shown below are approximate and were taken from a variety of sources. When dealing with liquid or gaseous hydrocarbons, the actual volume, weight, mass, or heat content may depend upon a range of factors such as the specific gravity of the fluid, the amount (if any) of water entrained in the mixture, the temperature and pressure at which the measurements are taken, and other factors. Consequently, in many cases there is no single factor that can be used for conversion. The factors below may be used as rules of thumb and will work for general comparison purposes or calculations.

Thermal conversion factors measure the equivalent heating content of various fuels in British Thermal Units (Btus). In the U.S., common practice is to use the gross or upper end of the range of heat content values for a specific product. In Europe, net or lower end heat content rates are typically used. The difference is the amount of energy that is consumed to vaporize the water created during the combustion process. This difference is typically 2 to 10%, depending on the specific fuel and its hydrogen content. Some fuels, such as unseasoned wood, can be more than 40% different in their gross and net heat content rates. [Source: U.S. Department of Energy, Energy Information Administration] Conversion tables included:

  • Volume
  • Mass/Weight
  • Length
  • Area
  • Energy
  • Approximate Heat Content of Petroleum Products
  • Million Btu (MMBtu) per Barrel

 

Volume

Unit Multiplied By Approximate Conversion Factor Equals Unit
Barrels of oil (bbl)
X
42
=
US gallons (gal)
Barrels of oil (bbl)
X
34.97
=
Imperial gallons (UK gal)
Barrels of oil (bbl)
X
0.136
=
Tonnes of oil equivalent (toe)
Barrels of oil (bbl)
X
0.1589873
=
Cubic meters (m3)
Barrels of oil equivalent (boe)
X
5,658.53
=
Cubic feet (f3) of natural gas
Tonnes of oil equivalent (toe)
X
7.33 [1]
=
Barrels of oil equivalent (boe)
Cubic yards (y3)
X
0.764555
=
Cubic meters (m3)
Cubic feet (f3)
X
0.02831685
=
Cubic meters (m3)
Cubic feet (f3) of natural gas
X
0.0001767
=
Barrels of oil equivalent (boe)
US gallons (gal)
X
0.0238095
=
Barrels (bbl)
US gallons (gal)
X
3.785412
=
Liters (l)
US gallons (gal)
X
0.8326394
=
Imperial gallons (UK gal)
Imperial gallons (UK gal)
X
1.201
=
US gallons (gal)
Imperial gallons (UK gal)
X
4.545
=
Liters (l)
[1] This conversion can range from 6.5 to 7.9 depending on the type of crude oil. This factor is intended to provide an approximation that can be used when the exact factor is unknown.

 

Mass/Weight

Unit Multiplied By Approximate Conversion Factor Equals Unit
Short tons
X
2,000
=
Pounds (lb)
Short tons
X
0.9071847
=
Metric tonnes (t)
Long tons
X
1.016047
=
Metric tonnes (t)
Long tons
X
2,240
=
Pounds (lb)
Metric tonnes (t)
X
1,000
=
Kilograms (kg)
Metric tonnes (t)
X
0.9842
=
Long tons
Metric tonnes (t)
X
1.102
=
Short tons
Pounds (lb)
X
0.45359237
=
Kilograms (kg)
Kilograms (kg)
X
2.2046
=
Pounds (lb)

 

Length

Unit Multiplied By Approximate Conversion Factor Equals Unit
Miles (mi)
X
1.609344
=
Kilometer (km)
Yards (yd)
X
0.9144
=
Meters (m)
Feet (ft)
X
0.3048
=
Meters (m)
Inches (in)
X
2.54
=
centimeters (cm)
Kilometer (km)
X
0.62137
=
miles (mi)

 

Area

Unit Multiplied By Approximate Conversion Factor Equals Unit
Acres
X
0.40469
=
Hectares (ha)
Square miles (mi2)
X
2.589988
=
Square kilometers (km2)
Square yards (yd2)
X
0.8361274
=
Square meters (m2)
Square feet (ft2)
X
0.09290304
=
Square meters (m2)
Square inches (in2)
X
6.4516
=
Square centimeters (cm2)

 

Energy

Unit Multiplied By Approximate Conversion Factor Equals Unit
British Thermal Units (Btus)
X
1,055.05585262
=
Joules (J)
Calories (cal)
X
4.1868
=
Joules (J)
Kilowatt hours (kWh)
X
3.6
=
Megajoules (MJ)
Therms
X
100,000
=
British thermal units (Btus)
Tonnes of oil equivalent
X
10,000,000
=
Kilocalories (kcal)
Tonnes of oil equivalent
X
396.83
=
Therms
Tonnes of oil equivalent
X
41.868
=
Gigajoules (GJ)
Tonnes of oil equivalent
X
11,630
=
Kilowatt hours (kWh)
Cubic feet (f3) of natural gas
X
1,025
=
British Thermal Units (Btus)

 

Approximate Heat Content of Petroleum Products Million Btu (MMBtu) per Barrel

Energy Source MMBtu/bbl Energy Source MMBtu/bbl
Crude Oil 5.800 Natural Gasoline 4.620
Natural Gas Plant Liquids 3.735 Pentanes Plus 4.620
Asphalt 6.636 Petrochemical Feedstocks:
Aviation Gasoline 5.048 Naphtha < 401° F 5.248
Butane 4.326 Other oils >= 401° F 5.825
Butane-Propane (60/40) Mixture 4.130 Still Gas 6.000
Distillate Fuel Oil 5.825 Petroleum Coke 6.024
Ethane 3.082 Plant Condensate 5.418
Ethane-Propane (70/30) Mixture 3.308 Propane 3.836
Isobutane 3.974 Residual Fuel Oil 6.287
Jet Fuel, Kerosene-type 5.670 Road Oil 6.636
Jet Fuel, Naphtha-type 5.355 Special Naphthas 5.248
Kerosene 5.670 Still Gas 6.000
Lubricants 6.065 Unfinshed Oils 5.825
Motor Gasoline - Conventional 5 5.253 Unfractionated Stream 5.418
Motor Gasoline - Oxygenated or Reformulated 5.150 Waxes 5.537
Motor Gasoline - Fuel Ethanol 3.539 Miscellaneous 5.796
Source: U.S. Department of Energy, Energy Information Administration (2001)