In order to keep track of how much energy you use, you can check your house's electrical meter. Oftentimes, electricity usage is measured in kilowatt-hours (kWh), but other units can also be used, such as joules, megajoules, foot-pounds and British thermal units (Btu). If your electrical meter reads in a different unit but your electric company charges by the kWh, convert your reading to know how much you will have to pay.

Divide the electrical meter reading in Btu by 3,413 Btu per kWh to convert to kWh. For example, if you have 30,000 Btu, divide 30,000 by 3,413 to get 8.7899 kWh.

Divide the number of joules by 3,600,000 joules per kWh. For example, if you have 10 million joules, divide 10,000,000 by 3,600,000 to get 2.78 kWh.

Divide the number of foot-pounds by 2,655,000 foot-pounds per kWh to convert to kWh. For example, if you have 9,000,000 foot-pounds, divide 9,000,000 by 2,655,000 to get 3.39 kWh.

Divide the number of megajoules by 3.6 megajoules per kWh to convert to kWh. For example, if you have 5 megajoules, divide 5 by 3.6 to get 1.39 kWh.