Convert between different units quickly and accurately in a modern way
Choose a Measurement
Select a measurement and convert between different units
Multiple conversions
To convert from Watt (W) to Milliwatt (mW), use the following formula:
To convert from Watt (W) to Kilowatt (kW), use the following formula:
To convert from Watt (W) to Megawatt (MW), use the following formula:
To convert from Watt (W) to Gigawatt (GW), use the following formula:
To convert from Watt (W) to Horsepower (metric) (PS), use the following formula:
To convert from Watt (W) to British thermal unit per second (Btu/s), use the following formula:
With is the ratio between the base units Foot-pound per second (ft-lb/s) and Watt (W).
To convert from Watt (W) to Foot-pound per second (ft-lb/s), use the following formula:
With is the ratio between the base units Foot-pound per second (ft-lb/s) and Watt (W).
To convert from Watt (W) to Horsepower (British) (hp), use the following formula:
With is the ratio between the base units Foot-pound per second (ft-lb/s) and Watt (W).
A watt (W) is the basic unit of power used to measure the rate of energy transfer.
In simple terms, it tells you how much energy a device uses per second. For example, a 60-watt light bulb uses 60 joules of energy every second.
In electrical systems, the formula is Watts = Volts × Amps.
The unit of power, the watt (W), is named in honor of James Watt, an 18th-century Scottish inventor and engineer.
His groundbreaking improvements to the steam engine were a key part of the Industrial Revolution. Naming the unit after him honors his major contributions to energy science.
Formally, a watt is defined as the rate of energy transfer equal to one joule per second.
In electrical systems, one watt is the power produced when a current of one ampere (A) flows through an electrical potential difference of one volt (V).
This fundamental relationship is a cornerstone of electrical engineering.
The relationship between power (P), voltage (V), and current (I) is expressed by the simple formula:
P = V × I
Where:
Understanding watts helps you see how much energy your common devices consume.
This is essential for comparing the energy efficiency of appliances and understanding your electricity bill. Here are some practical examples:
By checking the wattage on your devices, you can get a better sense of which ones use the most power in your home.