Watt (W) - Unit Information & Conversion

Symbol:W
Plural:watts
Category:Power

🔄 Quick Convert Watt

What is a Watt?

The watt is the SI unit of power, measuring the rate of energy transfer. Named after James Watt, it equals one joule per second and is widely used for electrical power ratings of appliances, light bulbs, and electronic devices.

History of the Watt

Named in 1882 after Scottish engineer James Watt (1736-1819) who improved the steam engine. Officially adopted as the SI unit of power in 1960. One watt was originally defined to relate to mechanical horsepower.

Watt Conversion Formulas

To Milliwatt:

1 W = 1000 mW
Example: 5 watts = 5000 milliwatts

To Kilowatt:

1 W = 0.001 kW
Example: 5 watts = 0.005 kilowatts

To Megawatt:

1 W = 0.000001 MW
Example: 5 watts = 0.000005 megawatts

To Gigawatt:

1 W = 1.0000e-9 GW
Example: 5 watts = 5.0000e-9 gigawatts

To Horsepower:

1 W = 0.001341 hp
Example: 5 watts = 0.006705 horsepower

To Metric Horsepower:

1 W = 0.00136 PS
Example: 5 watts = 0.006798 PS

To Electric Horsepower:

1 W = 0.00134 hp(E)
Example: 5 watts = 0.006702 hp(E)

To BTU per Hour:

1 W = 3.412142 BTU/h
Example: 5 watts = 17.060708 BTU/h

To BTU per Minute:

1 W = 0.056869 BTU/min
Example: 5 watts = 0.284345 BTU/min

To BTU per Second:

1 W = 0.000948 BTU/s
Example: 5 watts = 0.004739 BTU/s

To Foot-pound per Second:

1 W = 0.737562 ft⋅lb/s
Example: 5 watts = 3.687811 ft⋅lb/s

To Foot-pound per Minute:

1 W = 44.253729 ft⋅lb/min
Example: 5 watts = 221.268645 ft⋅lb/min

To Calorie per Second:

1 W = 0.239006 cal/s
Example: 5 watts = 1.195029 cal/s

To Kilocalorie per Hour:

1 W = 0.860421 kcal/h
Example: 5 watts = 4.302103 kcal/h

To Ton of Refrigeration:

1 W = 0.000284 TR
Example: 5 watts = 0.001422 TR

To Erg per Second:

1 W = 10000000 erg/s
Example: 5 watts = 50000000 erg/s

To Joule per Second:

1 W = 1 J/s
Example: 5 watts = 5 J/s

Convert Watt

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