Watts to Megawatts (W to MW) Converter

When dealing with large-scale energy systems, power is often expressed in megawatts rather than watts. While watts are suitable for everyday devices like lamps or fans, megawatts are used to describe the massive output of power plants, wind farms, and national grids.

This guide will walk you through the conversion from watts to megawatts, with clear formulas, tables, and practical examples to make the process straightforward.

Definitions of Watt and Megawatt

Let’s get started by understanding the key definitions of Watt (W) and Megawatt (MW). Understanding these terms will allow you to perform conversions confidently.

What is Watt?

The Watt (W) is an SI derived unit of power, equal to one joule per second (J/s).^[1]

Mathematically 1 W = 1 j/s:

$$\boxed{1 \,\text{Watt} = 1 \,\frac{\text{Joule}}{\text{Second}}}$$

Where:

j = joule unit of energy
s = second unit of time

According to SI prefixes^[2], which are based on powers of 10, a watt (1 W) is equivalent to one millionth of a megawatt (10^-6 MW or 0.000001 MW).

Megawatts to Watts Conversion Scale — Megawatts to watts conversion scale

Watt measurement unit is widely used to quantify electrical, mechanical, and thermal power in everyday applications such as light bulbs, appliances, and motors.

What is a Megawatt (MW)?

A megawatt (MW) is a unit of power in the SI system equal to one million watts (1,000,000 W).

Definition and Scale of Megawatt (MW) — Definition and scale of a megawatt (MW)

Megawatts are commonly used to express very large power levels, such as the output of power stations, wind farms, or the capacity of national electrical grids. For example, a typical onshore wind turbine may generate around 2 to 3 MW of power.

W to MW formula

Let’s take a closer look at the conversion formula so you can carry out these conversions independently, whether using a calculator or doing it manually with pencil and paper.

SI Prefixes and Values — SI multiples and submultiples

The mega- prefix in the International System of Units (SI) represents a multiplier of 10⁶ (1,000,000). So, to convert from watts to megawatts, divide the number of watt (P_(W)) by 1,000,000.

P_(MW) = P_(W) ÷ 1,000,000

\text{P}_\text{(MW)} = \frac{\text{P}_\text{(W)}}{1{,}000{,}000}

Or remember the W-to-MW conversion factor: 1 W = 0.000001 MW

W to MW conversion table

The conversion table below provides a handy reference for converting power measurement units from watts (W) to megawatts (MW). It covers commonly available power values, allowing for easy and quick conversions between these units of measurement.

Watts (W)	Megawatts (MW)
1 W	0.000001 MW
1,000 W	0.001 MW
100,000 W	0.1 MW
500,000 W	0.5 MW
1,000,000 W	1 MW
2,000,000 W	2 MW
4,000,000 W	4 MW
5,000,000 W	5 MW
10,000,000 W	10 MW
20,000,000 W	20 MW
30,000,000 W	30 MW
40,000,000 W	40 MW
50,000,000 W	50 MW
60,000,000 W	60 MW
70,000,000 W	70 MW
80,000,000 W	80 MW
90,000,000 W	90 MW
100,000,000 W	100 MW
200,000,000 W	200 MW
500,000,000 W	500 MW
800,000,000 W	800 MW
1,000,000,000 W	1,000 MW

Watts (W) to megawatts (MW) conversion table

Examples

Now, let's look at an example that illustrates the calculations required to convert from watts to megawatts (W to MW).

Example: Power Plant Output

Suppose you’re analyzing the output of a small hydroelectric power plant, and the datasheet specifies a power generation capacity of twenty five million watts (25,000,000 W). However, grid operators typically measure power in megawatts (MW).

Solution

Since 1 MW = 1,000,000 W, we can convert 25,000,000 W to megawatts by using the following formula:

$$\text{P}_\text{(MW)} = \frac{\text{P}_\text{(W)}}{1{,}000{,}000}$$

$$\text{P}_\text{(MW)} = \frac{25{,}000{,}000}{1{,}000{,}000} = \boxed{25 \text{ MW}}$$

Therefore, the hydroelectric plant generates 25 MW of power.

To solve the problem with our calculator, follow the steps below:

Enter the value in watts: For this example, enter 25000000 into the From box.
View the result: The converter instantly calculates and displays the equivalent value in megawatts: 25 MW.

Watts to Megawatts (W to MW) conversion example — Steps to convert from watts to megawatts with our calculator

FAQs

Is 1 watt or 1 megawatt larger?

A megawatt (MW) is a million times larger than a watt (W). Here are the relationships between the units:

1 MW = 10⁶ = 1,000,000 W
1 W = 10^-6 = 1 ÷ 1,000,000 = 0.000001 MW

How to convert from watts to megawatts?

To convert power from watts (W) to megawatts (MW), follow these simple steps:

Write down the power value in watts (W).
Divide it by 1,000,000.
The result is the power in megawatts (MW).

Why do I need to convert watts to megawatts?

Converting watts to megawatts is essential in energy management and infrastructure planning. For example, national power grids, wind farms, and industrial-scale generators are rated in megawatts to simplify calculations and comparisons.

You now know how to convert power units from watts (W) to megawatts (MW). You can quickly use our calculator to convert between the power measurement units to save time for future calculations.