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Power Converter

Watts, kilowatts, horsepower, and BTU/h.

Inputs

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Formula

result = value × (from.toBase ÷ to.toBase) with watt as base

Power is energy per time — joules per second. Mechanical horsepower (US) is 745.7 W; metric horsepower (PS) is 735.5 W; air conditioners sometimes quote BTU/h, which converts to watts for electrical load estimates.

Worked example

1 US horsepower ≈ 0.746 kW — the figure car brochures use when converting engine hp to electric motor kW equivalents.

Where this can give the wrong answer

  • US hp and metric hp differ by about 1.4% — pick the label that matches your spec sheet (hp vs PS).
  • BTU/h is a power rate, not an energy total — multiplying by hours gives energy (then use the energy converter).
  • Electrical 'VA' (volt-ampere) apparent power isn't listed; this tool is real power in watts.

FAQ

Power is the rate (watts = joules per second). Energy is the total consumed over time (kWh on a bill). A 100 W bulb running 10 hours uses 1 kWh of energy.

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