You can measure sizable amounts of household energy using the therm, which is equivalent to 100,000 British thermal units. When measuring the energy from natural gas, however, you can also use cubic feet. To produce 1 therm of energy, you need to use about 96.7 cubic feet of natural gas. Converting between these two units will help you make sure you plan for the appropriate amount of natural gas for your energy needs.
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Divide the cubic feet of natural gas by 96.7 to convert to therms. For example, if you have 400 cubic feet, divide 400 by 96.7 to get 4.14 therms.

Multiply the number of cubic feet of natural gas by 0.0103412 to convert to therms. This method will yield the same result. In this example, multiply 400 by 0.0103412 to get 4.14 therms.

Multiply the number of cubic feet by 96.7 to convert back to therms and verify your answer. In this example, multiply 4.14 therms by 96.7 to get about 400 cubic feet.
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