Natural Gas Converter (m³, ft³, CCF, MCF ↔ MJ, kWh, therms, MMBtu)

Understanding the natural gas converter — concept and principle

This converter changes natural gas quantities between volume units (cubic metres, cubic feet, CCF, MCF) and energy units (megajoules, gigajoules, kilowatt-hours, therms, Btu, MMBtu), using the gas's heating value. It also shows the result in all energy units, the volume in m³ and ft³, and the heating value in Btu per cubic foot. Households, facility managers and energy students use it to compare bills and fuels.

Gas volume × heating value — with the default inputs: 1,073.33 kWh.

How it is calculated

Energy = volume × heating value; volume = energy ÷ heating value
Volume factors: 1 ft³ = 0.028316846592 m³; 1 CCF = 100 ft³; 1 MCF = 1,000 ft³
Energy factors: 1 kWh = 3.6 MJ; 1 Btu (IT) = 1,055.05585262 J; 1 MMBtu = 10⁶ Btu; 1 US therm = 105.4804 MJ
Conversions between two volume units or two energy units do not need the heating value

Default heating value: 38.64 MJ/m³, the US 2025 average of 1,037 Btu/ft³.

The principle

A cubic metre of gas is a volume; what it can deliver is energy, and that depends on its composition. The heating value links the two. Pipeline natural gas typically has a gross (higher) heating value close to 38–40 MJ/m³. The gross value includes the heat recovered by condensing the water vapour in the flue gas; the net (lower) value excludes it. Bills that state "standard" cubic metres or apply a pressure and temperature correction should be converted with the corrected volume.

Worked example

Defaults: 100 m³ to kWh, heating value 38.64 MJ/m³.

Energy = 100 × 38.64 = 3,864 MJ.
kWh = 3,864 ÷ 3.6 = 1,073.33 kWh.
Therms = 3,864 ÷ 105.4804 = 36.632; MMBtu = 3.6624.
Volume = 100 m³ (100) = 100 ÷ 0.0283168 = 3,531.47 ft³.
Heating value = 1,037 Btu/ft³.

Each point is the calculator re-run with only “Amount to convert” changed; the gold point is the default example. Change the inputs above and this chart follows your numbers.

Amount to convert	Result
25	268.333 kWh
50	536.667 kWh
75	805 kWh
100	1,073.33 kWh
125	1,341.67 kWh
150	1,610 kWh
200	2,146.67 kWh

How to read the result

The kWh figure lets you compare gas with electricity on an energy basis. Divide your gas price per kWh by appliance efficiency to compare useful heat. Check the heating value on your bill; using a generic value can shift results by a few percent.

Common mistakes

Using a generic heating value instead of the bill's figure.
Mixing gross and net heating values.
Ignoring the volume correction factor on bills.
Comparing gas and electricity without appliance efficiency.

Keep in mind: Heating values vary by supplier and month. For billing disputes, rely on your supplier's stated figures and local regulations.

Frequently asked questions

How many kWh is 1 m³ of natural gas?

About 10.7 kWh at 38.64 MJ/m³; it depends on the gas's heating value.

What is a therm?

100,000 Btu, about 105.5 MJ or 29.3 kWh.

What is the difference between gross and net heating value?

Gross includes the heat from condensing water vapour in the exhaust; net does not.

Sources: U.S. Energy Information Administration, FAQ "What are Ccf, Mcf, Btu, and therms?" · NIST Special Publication 811 (2008 ed.), Appendix B.9

Checked 9 Nov 2026. U.S. Energy Information Administration, FAQ “What are Ccf, Mcf, Btu, and therms?” (2025 average heat content about 1,037 Btu per cubic foot); NIST Special Publication 811 (2008 ed.), Guide for the Use of the International System of Units (SI), Appendix B.9 “Factors for units listed by kind of quantity or field of science” — British thermal unit IT, therm (U.S.) = 1.054 804 E+08 J, cubic foot, kilowatt hour = 3.6 E+06 J.

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