Power Converter

Convert between Watt, Kilowatt, Megawatt, Horsepower and more

Free online power unit converter supporting 5 units: Watt (W), Kilowatt (kW), Megawatt (MW), Horsepower (HP), BTU/h. Real-time conversion with high precision. No registration required.

How to Use

Simple 3-step process to convert power units:

Step 1: Enter Value
Enter the power value in any unit field (Watt, Kilowatt, Megawatt, Horsepower, or BTU/h)
Step 2: Automatic Conversion
All other unit fields will be automatically converted in real-time
Step 3: Copy Results
Copy the converted values you need for your calculations

All conversions are performed in your browser. No data is sent to our servers.

Power Converter Tool

Watt (W)

Kilowatt (kW)

Megawatt (MW)

Horsepower (HP)

BTU per Hour (BTU/h)

Practical Use Cases

Power converters are essential in various fields:

1. Household Appliances

Compare electricity consumption. A typical LED bulb uses 10W, microwave 1000W (1kW), air conditioner 2000W (2kW). Understanding power ratings helps estimate electricity bills and choose energy-efficient appliances.

2. Electric Motors and Vehicles

Motor specifications often use horsepower. A car engine might be rated at 150HP ≈ 112kW. Electric vehicles use kilowatts (Tesla Model 3: 225kW ≈ 302HP). Converting between units helps compare performance across different rating systems.

3. HVAC Systems

Air conditioning and heating systems often use BTU/h. A 12,000 BTU/h AC ≈ 3.5kW. Converting to kilowatts helps calculate electricity costs. Industrial systems use megawatts for large-scale climate control.

4. Power Plants and Electricity Generation

Power plants rate capacity in megawatts (MW). A wind turbine produces 2-3MW. A nuclear plant produces 1000MW (1GW). Solar panels rate in watts (300W per panel). Understanding these conversions helps with energy planning.

5. Industrial Machinery

Heavy machinery uses various power ratings. Industrial compressors: 50-200HP (37-150kW). Conveyor systems: 5-20kW. Pumps: 1-100HP. Converting units ensures proper equipment selection and electrical infrastructure planning.

What is Power Conversion?

Power measures the rate of energy transfer. Different industries use different units, making conversion essential.

Common Power Units

Watt (W) is the SI unit of power: 1 Watt = 1 Joule per second. Kilowatt (kW) is 1000 watts, commonly used for household appliances and vehicles. Megawatt (MW) is one million watts, used for power plants and industrial facilities. Horsepower (HP) is an imperial unit: 1 HP ≈ 745.7W, traditionally used for engines and motors. BTU/h (British Thermal Unit per hour) measures heating/cooling capacity: 1 BTU/h ≈ 0.293W.

Why Convert Power Units?

Different countries and industries use different power units. North America often uses horsepower for engines. Most of the world uses kilowatts for electrical systems. HVAC systems traditionally use BTU/h. Converting between units helps compare products, calculate electricity costs, and understand equipment specifications across different markets.

Conversion Accuracy

This converter uses exact conversion factors: 1 W = 0.001 kW = 0.000001 MW = 0.00134102 HP = 3.41214 BTU/h. All conversions are mathematically exact with no approximations. Results are provided with up to 10 decimal places for engineering precision.

Frequently Asked Questions

How many watts are in a kilowatt?

1 kilowatt (kW) = 1000 watts (W). This is an exact conversion. For example, a 2kW heater uses 2000W. Household electricity bills are typically measured in kilowatt-hours (kWh), which is energy, not power.

How do I convert horsepower to kilowatts?

Multiply horsepower by 0.7457 to get kilowatts: HP × 0.7457 = kW. For example: 100 HP × 0.7457 = 74.57 kW. Conversely, divide kilowatts by 0.7457 to get horsepower: 50 kW ÷ 0.7457 ≈ 67.05 HP. This uses mechanical horsepower (745.7W).

What is the difference between kW and kWh?

kW (kilowatt) measures power - the rate of energy use. kWh (kilowatt-hour) measures energy - the total amount used over time. A 1kW heater running for 1 hour uses 1kWh of energy. Power × Time = Energy. Your electricity bill charges for kWh (energy), not kW (power).

How many BTU per hour equals one kilowatt?

1 kilowatt (kW) = 3412.14 BTU/h. This conversion is commonly used for air conditioners and heaters. A 12,000 BTU/h AC unit ≈ 3.5 kW. To convert: BTU/h ÷ 3412.14 = kW, or kW × 3412.14 = BTU/h.

Why are there different types of horsepower?

There are three main types: Mechanical HP (745.7W, US/UK standard), Metric HP (735.5W, European standard), and Electrical HP (746W). This converter uses mechanical horsepower (745.7W), the most common standard. The differences are small (about 1-2%).

How do I calculate electricity costs from power rating?

Formula: Cost = Power (kW) × Hours × Price per kWh. Example: A 1500W (1.5kW) heater running 4 hours at $0.12/kWh costs: 1.5 × 4 × 0.12 = $0.72. Convert watts to kilowatts first: W ÷ 1000 = kW.

What is a megawatt used for?

Megawatts (MW) measure large-scale power: Wind turbines (2-3 MW each), Solar farms (1-100 MW), Nuclear plants (1000 MW = 1 GW), Small towns (5-10 MW), Data centers (10-100 MW). 1 MW = 1000 kW = 1,000,000 W.

How accurate is this power converter?

This converter uses exact conversion factors with up to 10 decimal places precision. Conversions between W, kW, and MW are exact (powers of 10). HP and BTU/h conversions use standard engineering values (HP: 745.7W, BTU/h: 0.293071W) with no approximations.