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Single conversion
To convert from Watt-hour (Wh) to Megajoule (MJ), use the following formula:
Let's convert 5 Watt-hour (Wh) to Megajoule (MJ).
Using the formula:
Therefore, 5 Watt-hour (Wh) is equal to Megajoule (MJ).
Here are some quick reference conversions from Watt-hour (Wh) to Megajoule (MJ):
| Watt-hours | Megajoules |
|---|---|
| 0.000001 Wh | MJ |
| 0.001 Wh | MJ |
| 0.1 Wh | MJ |
| 1 Wh | MJ |
| 2 Wh | MJ |
| 3 Wh | MJ |
| 4 Wh | MJ |
| 5 Wh | MJ |
| 6 Wh | MJ |
| 7 Wh | MJ |
| 8 Wh | MJ |
| 9 Wh | MJ |
| 10 Wh | MJ |
| 20 Wh | MJ |
| 30 Wh | MJ |
| 40 Wh | MJ |
| 50 Wh | MJ |
| 100 Wh | MJ |
| 1000 Wh | MJ |
| 10000 Wh | MJ |
For all Energy converters, choose units using the From/To dropdowns above.
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.
Ever looked at a food label outside the US or heard about the energy of a lightning bolt and seen the term 'megajoule' or 'MJ'?
What exactly is it?
In this simple guide, we'll break down what a megajoule is, how big it is, and where you'll see it used in everyday life and science.
A Megajoule (MJ) is a unit of energy in the International System of Units (SI), equal to one million Joules (106 J).
The plural form is Megajoules.
To visualize the energy in a single megajoule, it helps to use a powerful real-world comparison.
One megajoule (1 MJ) is roughly the same as the kinetic energy of a one-tonne car traveling at 160 km/h (about 100 mph).
This comparison shows just how much energy a single megajoule represents, making it a key unit for measuring large energy transfers in fields like physics and engineering.
In many countries, including Australia and New Zealand, the megajoule (MJ) and kilojoule (kJ) are the standard units on nutritional labels to measure the energy content of food, instead of Calories (kcal).
To understand these labels, it's helpful to know the conversion:
One megajoule (MJ) is equal to approximately 239 food Calories (kcal).
This makes the MJ a critical unit for international dietary and health management.
The megajoule is a common unit for quantifying large-scale energy events and outputs in science and technology.
For example: