⚡ Power Converter
Microwave says 1200 W, car says 150 hp, furnace says 50,000 BTU/h. All are power — energy per second — but wildly different numbering.
Last updated — conversions use exact ISO unit definitions.
How it works
All power conversions route through the watt (W = 1 joule per second). The key distinction is between mechanical horsepower (1 hp = 745.7 W) and metric horsepower (1 PS = 735.5 W), sometimes called "pony power" or "CV" in Europe. They differ by about 1.4%.
Kilowatts (kW) are standard in the US for car engines now, but Europe still uses PS/hp interchangeably. One kW ≈ 1.341 hp (mech) ≈ 1.360 PS (metric). Electric motors are rated in kW; IC engines in hp or PS depending on region.
BTU/h and calories/min are thermal power units. 1 kW ≈ 3,412 BTU/h ≈ 143.3 cal/min. Furnaces and air conditioners use BTU/h; industrial heating may use kW.
Watt vs horsepower
1 mechanical hp = 745.7 W. 1 metric hp (PS) = 735.5 W. James Watt coined the term in 1775 as a marketing number — roughly how much work a horse could do per hour. Two conflicting definitions persist.
How accurate are these conversions?
All conversions use ISO 80000 standard unit definitions. For example, 1 inch = 2.54 centimeters exactly by international agreement.
Why can't I see all units on mobile?
The result table scrolls horizontally. The headline pair above shows the most commonly requested conversion.
Do you store my inputs?
No. All calculations happen in your browser. We collect zero personal data.
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