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To convert from Kilojoule (kJ) to Watt-hour (Wh), use the following formula:
Let's convert 5 Kilojoule (kJ) to Watt-hour (Wh).
Using the formula:
Therefore, 5 Kilojoule (kJ) is equal to Watt-hour (Wh).
Here are some quick reference conversions from Kilojoule (kJ) to Watt-hour (Wh):
| Kilojoules | Watt-hours |
|---|---|
| 0.000001 kJ | Wh |
| 0.001 kJ | Wh |
| 0.1 kJ | Wh |
| 1 kJ | Wh |
| 2 kJ | Wh |
| 3 kJ | Wh |
| 4 kJ | Wh |
| 5 kJ | Wh |
| 6 kJ | Wh |
| 7 kJ | Wh |
| 8 kJ | Wh |
| 9 kJ | Wh |
| 10 kJ | Wh |
| 20 kJ | Wh |
| 30 kJ | Wh |
| 40 kJ | Wh |
| 50 kJ | Wh |
| 100 kJ | Wh |
| 1000 kJ | Wh |
| 10000 kJ | Wh |
For all Energy converters, choose units using the From/To dropdowns above.
A kilojoule (kJ) is a unit used to measure energy.
Just like a kilometer is 1,000 meters, a kilojoule is 1,000 joules. Kilojoules are part of the International System of Units (SI), the modern form of the metric system.
They are used worldwide to measure energy in food, physics, and everyday life.
Key Takeaways:
In nutrition, kilojoules (kJ) are the international standard for measuring the energy we get from food and drinks.
You'll often see them listed alongside calories (cal) on nutrition labels, especially outside of the United States.
Understanding the relationship between them is easy. The conversion is simple: 1 calorie is about 4.2 kilojoules.
Knowing this helps you accurately track your energy intake and easily compare food products, no matter where you are in the world.
As a multiple of the joule, the kilojoule (kJ) is a fundamental unit for measuring work and energy in scientific fields like physics and chemistry.
One kilojoule (1,000 joules) is roughly the energy needed to lift a 100-kg (220-lb) object one meter off the ground.
This standardization allows scientists to make precise and consistent energy calculations in experiments and research.
Beyond food labels and science labs, kilojoules help quantify the energy we use for everyday activities and appliances.
Thinking in kilojoules offers a practical way to understand and manage your personal energy expenditure.
For example:
Ever looked at the back of a battery pack and felt confused by the numbers? You're not alone!
One of the most important measurements you'll see is the Watt-hour (Wh).
Think of it as the fuel gauge for your electronic devices. This simple guide will break down precisely what a Wh is and why it matters.
A Watt-hour (Wh) is a unit that measures energy. Specifically, it tells you how much energy a device uses over a specific period.
The concept is simple: one Watt-hour is the amount of energy consumed when one watt of power is used for precisely one hour.
A helpful analogy is a car's gas tank. The Watt-hour rating on a battery is like the size of the tank—it tells you the total amount of energy it can store.
The power your device draws (measured in Watts) is like how fast you're driving and using up that gas.
A battery with a higher Wh rating holds more energy and can power your device for longer, just like a larger gas tank lets you drive farther.
You'll find Wh ratings on many of the rechargeable devices you use daily. It's a key indicator of battery capacity and runtime. Some common examples include:
The Watt-hour is directly related to the joule (J), which is the standard scientific unit for energy. The conversion is straightforward:
This is because a watt is defined as one joule per second, and there are 3,600 seconds in an hour (60 seconds × 60 minutes).
A kilowatt-hour (kWh) is simply 1,000 Watt-hours. The prefix "kilo-" means one thousand.
You're probably most familiar with kWh from your home electricity bill. Utility companies use this larger unit to measure your household's monthly energy consumption.
So, when you see that you used 500 kWh last month, it means you used 500,000 Watt-hours of energy.