Power Converter

A power converter is a tool that transforms a measurement of power expressed in one unit into its equivalent value in another unit. Power is the rate at which energy is transferred or work is done — defined in SI as the watt (W), equal to one joule per second. When you use a power converter, you rely on fixed conversion factors that define how units relate to each other. For example, 1 kilowatt = 1000 watts exactly, and 1 mechanical horsepower = 745.69987 watts. Our power converter applies these exact factors across SI units (W, kW, MW, GW), horsepower variants (mechanical, metric, electric), thermal units (BTU/hr, BTU/min, BTU/s), mechanical units (ft·lbf/s), and electrical units (VA, kVA, dBm) — covering 20 units in total.

1. 1. Select Your Units: Choose your source unit (e.g. Kilowatt) and target unit (e.g. Horsepower — Mechanical) from the dropdowns. Use the swap button (⇄) to instantly reverse the conversion direction without manually changing dropdowns.
2. 2. Enter Your Value: Type the power value you want to convert. The power converter accepts any numeric value including decimals and very large numbers. All processing happens locally in your browser — your data never leaves your device.
3. 3. Get Instant Results: Click Convert and the power converter instantly displays the converted value with up to 8 decimal places. The quick-reference table shows your value converted to all 7 common power units simultaneously.

• Mechanical Horsepower (hp): The most common definition in the United States, equal to exactly 745.69987 watts. Originally defined by James Watt as the power of a horse lifting 550 foot-pounds per second. Used for car engines, pumps, and motors in the US market.
• Metric Horsepower (PS / CV / ch): Used in Europe and Asia, equal to exactly 735.49875 watts — the power needed to lift 75 kilograms by 1 meter per second. European car specifications typically use PS (Pferdestärke in German). Our power converter distinguishes this from mechanical hp to avoid the ~1.4% error between the two.
• Electric Horsepower (hp): Defined as exactly 746 watts by the IEEE. Used for electric motors and generators in the US. The difference from mechanical hp is small (~0.04%) but matters for precise electrical engineering calculations.
• dBm (decibel-milliwatt): A logarithmic unit used in RF and telecommunications. 0 dBm = 1 milliwatt. Our power converter handles the logarithmic conversion: P(W) = 10^((dBm − 30) / 10), making it accurate for signal power calculations.

Our power converter uses exact, internationally recognized conversion factors. The base-unit method converts all values through watts first, then to the target unit, ensuring consistent accuracy across all unit pairs. The dBm unit uses the correct logarithmic formula rather than a linear approximation. Results are displayed with up to 8 decimal places for values in the normal range, and in scientific notation for very large or very small values. The quick-reference table updates live as you type, showing your input value converted to 7 common power units simultaneously.