Power Converter

In the world of physics, power is defined as the rate at which work is done or energy is transferred over time. Whether you are measuring the electricity consumed by a household LED lightbulb, the mechanical force generated by a car engine, or the cooling capacity of your living room air conditioner, you are measuring power.

Because power is measured across drastically different industries globally, we have inherited several different units of measurement. Electricians and physicists rely heavily on the metric system's Watts (W) and Kilowatts (kW), while the automotive, agricultural, and heavy machinery industries in India still heavily rely on Horsepower (HP). Furthermore, the HVAC (heating and cooling) industry often uses thermal measurements like BTUs per hour.

Our free, precision Power Converter tool eliminates the confusion of complex manual calculations. Whether you are comparing car engine specifications, buying a new home water pump, or calculating the power draw of industrial equipment, this calculator handles over a dozen global power units instantly.

How to Use the Power Converter

This calculator lets you instantly convert a power value from one unit of measurement to another. Here is a step-by-step guide to using the tool:

Enter the Value: Type the specific numerical value of the power you wish to convert in the "Value" box.
Select 'From Unit': Choose the unit you are starting with from the first dropdown menu.
Select 'To Unit': Choose the unit you want to convert the value into from the second dropdown menu. The conversion will display instantly.

Supported Power Units

We categorize our supported units into three main groups: Electrical, Mechanical, and Thermal/Work rate.

Electrical (SI Units)

Watts (W)
Kilowatts (kW)
Megawatts (MW)

Mechanical Units

Imperial Horsepower (hp)
Metric Horsepower (PS/cv)

Understanding Power Conversions & Formulas

The Watt (W) is the fundamental unit of power in the International System of Units (SI). One Watt is defined mathematically as one Joule of energy transferred per second (1 W = 1 J/s). Because a single Watt is a very small amount of power, it is usually scaled up for household appliances (Kilowatts) and national power grids (Megawatts and Gigawatts).

Electrical Power: Watts and Kilowatts

Kilowatts to Watts: Multiply kW by 1,000.
(Example: A 1.5 kW electric kettle uses 1,500 Watts)
Megawatts to Kilowatts: Multiply MW by 1,000.
(Example: A 2 MW wind turbine generates 2,000 kW)
Watts to Kilowatts: Divide W by 1,000.
(Example: A 60 W ceiling fan consumes 0.06 kW)

Mechanical Power: Horsepower (hp)

The term "horsepower" was famously coined by engineer James Watt in the 18th century to compare the output of his newly invented steam engines with the physical pulling power of draft horses. Today, we have two different definitions of horsepower depending on your region:

Imperial / Mechanical Horsepower (hp)

Used heavily in the United States, UK, and traditionally in India for water pumps and older machinery. 1 hp = 745.7 Watts.

hp to Watts: Multiply hp by 745.7
hp to Kilowatts: Multiply hp by 0.7457.
Kilowatts to hp: Multiply kW by 1.341.

Metric Horsepower (PS or cv)

Used widely by modern European and Asian car manufacturers. Written as PS (Pferdestärke) or cv (cheval-vapeur). 1 PS = 735.5 Watts.

PS to Watts: Multiply PS by 735.5
Kilowatts to PS: Multiply kW by 1.360.

Practical Math Examples in Daily Life

Example 1: Buying a Home Water Pump

Scenario: You are buying a residential water pump in India. The shopkeeper tells you it has a 1.5 HP (Imperial) motor. You want to know how many Watts it consumes to check if your home inverter can support it.

Identify the formula: 1 Imperial hp = 745.7 Watts.
Set up the calculation: Multiply the motor horsepower by the Watt conversion factor.
Calculate: 1.5 x 745.7 = 1,118.55 Watts.

Conclusion: The 1.5 HP water pump will draw approximately 1,118 Watts (or 1.1 kW) of electricity.

Example 2: Understanding Car Engine Specifications

Scenario: You are comparing two cars. Car A generates 120 PS (Metric Horsepower). Car B's brochure says it generates 85 Kilowatts (kW). You need to convert Car B's power into PS to make a fair comparison.

Identify the formula: To convert kW to Metric HP (PS), multiply the kW by 1.360.
Calculate: 85 kW x 1.360 = 115.6 PS.

Conclusion: Car B generates 115.6 PS. Therefore, Car A (120 PS) has a slightly more powerful engine than Car B.

Frequently Asked Questions

How many Watts are in one Horsepower (HP)?▼

One Imperial (Mechanical) Horsepower is exactly equal to 745.7 Watts. However, if you are using Metric Horsepower (PS/cv), one metric HP equals 735.5 Watts.

What is the difference between kW and kVA?▼

Kilowatts (kW) represent real power—the actual power consumed by an appliance to do work. Kilovolt-Amperes (kVA) represent apparent power, which is the total power supplied by the grid. For highly efficient appliances, kW and kVA are nearly identical, but in industrial motors, kVA is usually higher.

Why is air conditioning cooling measured in BTU or Tons instead of Watts?▼

BTU (British Thermal Unit) measures heat extraction over time (BTU/hour). While you can measure an AC's cooling power in Watts, the HVAC industry historically standardized on BTU and Refrigeration Tons. One Ton of cooling is equal to 12,000 BTU/hr, which converts to roughly 3,516 Watts of thermal power.

What is the difference between Imperial and Metric Horsepower?▼

Imperial Horsepower (used in the US, UK, and often India) defines the power needed to lift 550 pounds by one foot in one second (745.7 W). Metric Horsepower (PS), used widely in Europe and Japan, defines the power to lift 75 kilograms by one meter in one second (735.5 W).

How do I calculate my home inverter capacity?▼

First, sum up the wattage of all the appliances you want to run simultaneously (e.g., 3 fans at 70W each + 2 lights at 10W each = 230W). Divide this total wattage by the power factor (usually 0.8) to get the required VA (Volt-Ampere) rating. So, 230W / 0.8 = 287.5 VA. You should buy an inverter with at least a 300 VA capacity.

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