Joules to Kilowatt-hours Converter
Enter the energy in joules below to convert it to kilowatt-hours.
Convert Joules to Kilowatt-hours
Enter a value in joules (J) to convert to kilowatt-hours (kWh).
Joule to Kilowatt-hour Conversion Table
Table showing various joule measurements converted to kilowatt-hours. Click any preset value or arrow to load it into the converter.
| Joules (J) | Kilowatt-hours (kWh) |
|---|---|
| 1 J | 0.000000278 kWh |
| 10 J | 0.000002778 kWh |
| 100 J | 0.000027778 kWh |
| 1,000 J | 0.000277778 kWh |
| 10,000 J | 0.0027778 kWh |
| 100,000 J | 0.0277778 kWh |
| 1,000,000 J | 0.2777778 kWh |
| 5,000,000 J | 1.3888889 kWh |
| 10,000,000 J | 2.7777778 kWh |
| 25,400,000 J | 7.0555556 kWh |
How to Convert Joules to Kilowatt-hours
To convert joules to kilowatt-hours, multiply the energy by the following conversion ratio: 0.000000278 kilowatt-hours/joule.
Since one joule is equal to 0.000000278 kilowatt-hours, you can use this simple formula to convert:
The energy in kilowatt-hours is equal to the energy in joules multiplied by 0.000000278.
For example, here's how to convert 5 joules to kilowatt-hours using the formula above.
How Many Kilowatt-hours Are in a Joule?
There are 0.000000278 kilowatt-hours in a joule, which is why we use this value in the formula above.
Our joule to kilowatt-hour calculator automatically converts your energy measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Joules and kilowatt-hours are both units used to measure energy. Keep reading to learn more about each unit.
What Is a Joule?
Coherent SI unit of energy and work (1 W·s = 1 N·m). It serves as a primary reference unit for measuring energy across scientific and practical applications. [1]
The joule is classified as an International System of Units (SI) unit of energy. Joules can be abbreviated as J; for example, 1 joule can be written as 1 J.
As the primary coherent reference unit for energy in this category, all other energy units are mathematically anchored to the joule (J).
In practice, joules (J) are widely used across standard energy applications within International System of Units (SI) workflows, engineering documentation, and technical data sheets.
What Is a Kilowatt-hour?
A kilowatt-hour is a unit of energy equal to 3,600,000 joules (J), the base unit for energy. Equal to 3.6 Megajoules (1,000 Wh). [2]
The kilowatt-hour is classified as a metric and SI-compatible unit of energy. Kilowatt-hours can be abbreviated as kWh; for example, 1 kilowatt-hour can be written as 1 kWh.
In the metric system, "kilo" is the standard SI prefix for thousands, or 10³. This makes the kilowatt-hour (kWh) a convenient decimal multiple of the joule (J).
In practice, kilowatt-hours (kWh) are widely used across large-scale industrial, bulk, and macro-level energy specifications within SI metric workflows, engineering documentation, and technical data sheets.
When converting energy between joules (J) and kilowatt-hours (kWh), keep full floating-point precision (1 J = 0.000000278 kWh; 1 kWh = 3,600,000 J) during intermediate calculations and round only the final kilowatt-hour figure to match your instrument tolerance.
More Joule & Kilowatt-hour Conversions
Need to calculate in the opposite direction? Use our kilowatt-hours to joules converter (kWh to J) to switch your starting unit immediately. You can also explore related tools such as converting btus to kilowatt-hours, converting ampere-hours to kilowatt-hours, or converting joules to calories.
Convert from Joules
Frequently Asked Questions
References
- [1]NIST CODATA StandardNIST CODATA (CODATA Energy & Thermodynamic Constants)·Energy Metrology Standard — Joules (J) to Kilowatt-hours (kWh)
- [2]NIST SP 811 SpecificationNIST SP 811 (NIST SP 811 App. B.9 (Energy, Work & Heat))·Unit Specifications: Joule (J) & Kilowatt-hour (kWh)
- [3]BIPM ReferenceBIPM (Derived SI Unit: Joule (J))·Conversion Factors & Mathematical Basis (J to kWh)