Free Online Power Converter
A power tool maps a value across watts, kilowatts, megawatts, mechanical hp, metric hp, BTU/hr and ft·lbf/s using the watt as the SI pivot.
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How to Use This Converter
- Pick the input unit, including which hp variant.
- Pick the target unit in the To dropdown.
- Type the power value; the result and 1-to-1 factor appear.
- Tap swap to flip direction.
What Is a Power Converter?
Power is the rate of energy transfer: 1 watt = 1 joule per second. Where it gets interesting is horsepower — there are two competing definitions still in active use. Mechanical (imperial) horsepower is 745.6999 W; metric (DIN) horsepower is exactly 735.49875 W. US car specs quote mechanical hp; German and Japanese spec sheets quote metric hp (Pferdestärke, PS). The two differ by about 1.4%, which is enough to matter when comparing engine output.
BTU/hr shows up on air-conditioner labels and heating equipment (1 BTU/hr ≈ 0.293 W, so a 12,000 BTU/hr unit is roughly 3.52 kW). Foot-pounds per second still appears in older mechanical engineering texts.
The tool lists both horsepower flavours separately so the user picks the right one, then normalises to watts internally.
Frequently Asked Questions
How many watts in a horsepower?
What is a kilowatt?
BTU/hr to watts?
Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.
Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.
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