Joules to Kilowatt-hours Converter
Convert Joules (J) to Kilowatt-hours (kWh) instantly, or use the conversion table below to look up common values.
Joules to Kilowatt-hours conversion table
| Joules (J) | Kilowatt-hours (kWh) |
|---|---|
| 1 | 2.7778e-7 |
| 2 | 5.5556e-7 |
| 3 | 8.3333e-7 |
| 4 | 1.1111e-6 |
| 5 | 1.3889e-6 |
| 10 | 2.7778e-6 |
| 25 | 6.9444e-6 |
| 50 | 1.3889e-5 |
| 100 | 2.7778e-5 |
How to convert Joules to Kilowatt-hours
1 J equals 2.7778e-7 kWh. Use the converter above for any value, or read the table for common conversions.
kWh = J × 2.7777777777777776e-7 · J = kWh × 3600000Multiply a joules figure by 2.7778e-7 to get kilowatt-hours, or divide it by 3,600,000 to go the other way.
Worked examples
- 1 J= 2.7778e-7 kWh
- 5 J= 1.3889e-6 kWh
- 10 J= 2.7778e-6 kWh
- 25 J= 6.9444e-6 kWh
- 100 J= 2.7778e-5 kWh
What these units are
Joules (J). The joule is the SI unit of energy: the work done by one newton over one meter. It is used for small energy amounts in physics and engineering.
Kilowatt-hours (kWh). A kilowatt-hour is 1,000 watt-hours, or 3.6 megajoules. It is the unit on electricity bills, and the 'unit' shown on a prepaid meter.
All factors are exact definitions, so only the display is rounded.
Converting Joules to Kilowatt-hours in practice
Working in joules
Energy in the International System of Units is measured in joules, where one joule is the work done by a force of one newton moving an object one metre. The symbol is J.
Physics and engineering use the joule for mechanical work, heat, radiation and electrical energy, and small appliance labels sometimes state a surge or pulse rating in joules.
Multiples of the joule such as the kilojoule and megajoule are exact powers of one thousand, so no precision is lost. A watt is a rate rather than an amount, so it must be multiplied by time to yield joules.
The usual slip is to quote an electricity meter reading in joules when the meter counts kilowatt-hours. Both name energy, but the joule figure is 3.6 million times the kilowatt-hour figure.
The joule is the base unit, the kilojoule and megajoule are its decimal multiples, and the kilowatt-hour is the accounting unit an electricity meter counts. Joules suit physics and small quantities, while kilowatt-hours suit billing and storage capacity.
Reading the result in kilowatt-hours
The kilowatt-hour is the energy of one kilowatt sustained for one hour, and it is exactly 3.6 megajoules. Its symbol is kWh, and it equals 1,000 watt-hours.
Electricity bills, prepaid meter units, solar generation totals and battery or power-bank capacity are all measured in kilowatt-hours. Appliance consumption over time is compared in the same unit.
A kilowatt-hour is an amount of energy and a kilowatt is a rate, so the unit already contains the time element. Multiplying a kilowatt rating by hours of use gives kilowatt-hours directly.
Quoting a battery in kilowatt-hours when the label gives only amp-hours and a voltage skips a step, because the two must be multiplied first. A kilowatt-hour and a kilowatt are also not interchangeable.
The kilowatt-hour is the meter's accounting unit, the watt-hour is its one-thousandth for battery labels, and the joule and megajoule express the same energy in physics and fuel data. A meter reading is rarely converted into joules, but the two describe one amount.
Checking a joules to kilowatt-hours conversion
Energy units are defined against the joule, so every conversion in this dimension is a single exact multiplication by a published number rather than a chain of steps that could accumulate error.
The pair that needs care is the kilowatt-hour, because it looks like a power unit and is not. It is a watt sustained for an hour, which is why an electricity meter counts in kilowatt-hours while a generator is rated in kilowatts: one is an amount, the other is a rate, and only a duration links them.
To check an energy conversion, express both sides in joules or both in kilowatt-hours before comparing. The commonest mistake is treating a food calorie as a calorie when the label means a kilocalorie, which understates the figure a thousandfold.
Tanzania reference points
Real quantities, converted into the units on this page.
One unit of electricity on a Tanzanian prepaid meter
1 kWh = 3,600,000 J
The average domestic rate was about 229.59 TZS per kWh as of December 2025, including taxes and supply. That is an average across domestic customers, not the marginal rate on a bill.
Source: GlobalPetrolPrices — Tanzania electricity prices (compiled from EWURA/TANESCO tariffs) · verified 2026-09-14
Related conversions
More energy conversions you can convert instantly.