Power Converter
Convert between watts, kilowatts, horsepower and BTU per hour.
What the Power Converter does
Power is the rate of energy transfer — one watt is one joule per second. Note that mechanical horsepower (745.7 W) differs slightly from metric horsepower or PS (735.5 W), which is why the same car has different figures in different markets.
Formula
Convert to watt, then divide by the target unit's factorResult = Value × (from factor ÷ to factor)
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Value | number | Yes | — |
| From | one of 7 options | Yes | — |
| To | one of 7 options | Yes | — |
How to use it
- Choose From and To.
- Enter Value.
- Select Calculate.
Worked example
Convert a 150 kW engine to horsepower.
- Value
- 150
- From
- Kilowatt
- To
- Horsepower
150,000 ÷ 745.7 = 201.2 hp.
Reading the result
- A watt is a joule per second, so power multiplied by time gives energy. A 2 kW heater run for three hours uses 6 kWh.
Common mistakes
- Assuming all horsepower is the same. Mechanical horsepower is 745.7 W and metric horsepower (PS) is 735.5 W, a 1.4% gap that appears when the same car is quoted in different markets.
- Confusing power with energy. Watts describe a rate; watt-hours describe an amount consumed.
Frequently asked questions
What is the difference between hp and PS?
Mechanical horsepower is 745.7 W; metric horsepower (PS or CV) is 735.5 W. PS figures read about 1.4% higher for the same engine.