Convert joules to kWh

One joule equals 0.0000002778 kilowatt-hours. To convert any number of joules to kilowatt-hours, multiply by 0.0000002778.

The converter above works in both directions and updates as you type. Below you will find the formula, a worked example and a reference table of common values.

Energy conversions sit between physics and the kitchen. The joule is the SI unit and the one every equation uses; the calorie survives on food labels, where it is actually a kilocalorie a thousand times larger than the physicist’s calorie; and the kilowatt-hour is what an electricity meter counts. All three measure the same quantity, which is why an appliance’s consumption and a meal’s energy content can, in principle, be compared directly.

joules to kWh formula

To go the other way, use joule = kilowatt-hour ÷ 0.0000002778.

About these units

The joule is the SI unit of energy: one newton acting over one metre, or one watt for one second. Every other energy unit here is defined against it.

The kilowatt-hour is the unit electricity is billed in worldwide: one kilowatt drawn for one hour, or 3.6 megajoules.

Joule is also written joules. Kilowatt-hour is also written kilowatt hours and units of electricity.

Sources

1. Bureau International des Poids et Mesures, The International System of Units (SI), 9th edition, 2019.