Power Converter

Convert between Watts, Horsepower, and BTUs per hour instantly. Perfect for engineering, automotive, and HVAC calculations.
4.6/5 (62 ratings) 👁 54 uses 🔄 Updated 07-03-2026
🔒 100% Private ⚡ Instant Results 🆓 Always Free
⚡ Power Converter Instant power unit conversions.

⚡ Power Converter 2026

1 horsepower (hp) = 745.7 watts, 1 BTU/hour = 0.293071 watts
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🔍 What Is Power Converter?

A Power Converter is a tool that translates measurements of power from one unit to another. Power is the rate at which energy is transferred or work is done. Common units include Watts (W) for electrical and mechanical power, Horsepower (hp) for engines and motors, and BTUs per hour (BTU/h) for heating and cooling systems. This converter handles these and often includes kilowatts (kW), megawatts (MW), and other related units. You enter a number, select the unit you have, and choose the unit you want. The tool calculates the equivalent value instantly.

Here is how it works. You type a number into the input field. You pick the unit of that number from a dropdown (like Horsepower). Then you pick the target unit (like Watts). The tool multiplies or divides using the correct conversion factor. For example, 1 horsepower = 745.7 watts. 1 BTU per hour ≈ 0.293 watts. The result appears immediately. You can copy it or clear and start over. Some converters also handle scientific notation for very large or small numbers.

Who uses this? Engineers use it constantly—mechanical, electrical, and automotive engineers all need to convert between power units. Mechanics use it to understand engine specs. HVAC technicians use it for heating and cooling calculations. Students use it for physics and engineering homework. Electricians use it for electrical load calculations. Homeowners use it when comparing appliance power ratings. Anyone dealing with motors, engines, heaters, or electrical devices encounters different power units.

Benefits are about accuracy and bridging different systems. A car engine might be rated in horsepower, but an electric motor in kilowatts. Comparing them requires conversion. The same for heating—furnaces are rated in BTUs, but heat pumps in watts. This tool eliminates mental math errors and saves time. It also helps with understanding scale. Seeing that 1 horsepower is about 746 watts gives perspective on the power of different devices. For international work, it's essential—different countries use different units.

Common use cases include:

  • Automotive: Converting engine power between hp and kW for comparisons.
  • HVAC: Converting heating/cooling capacity between BTU/h and watts.
  • Electrical engineering: Converting between watts, kilowatts, and megawatts.
  • Mechanical engineering: Converting between horsepower and watts for motor specs.
  • Physics homework: Solving problems involving different power units.
  • Appliance shopping: Comparing power consumption across different unit systems.

The tool typically includes: watt (W), kilowatt (kW), megawatt (MW), mechanical horsepower (hp), metric horsepower (PS), BTU per hour (BTU/h), and sometimes tons of refrigeration. It handles both small and large numbers with ease. All calculations are done in your browser for privacy—your data is not sent to any server.

⚡ How To Use - Step by Step

1
Enter Power Value — Input the numeric value you wish to convert and select the starting unit from the list.
2
Process Instantly — The tool automatically calculates the equivalent power across all other major units simultaneously.
3
Copy Result — Select the converted unit you need and copy it to your clipboard for your calculations.

🌟 Key Features

Multiple Units
Watts, kilowatts, megawatts, horsepower (mechanical & metric), BTU/h, and more.
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Accurate Factors
Uses standard conversion factors (1 hp = 745.7 W, 1 BTU/h = 0.293071 W).
📱
Instant Results
Conversion updates as you type or change units.
🚀
Scientific Notation
Handles very large and very small numbers.
🎯
Client-Side
All calculations in your browser. Private.

👥 Who Can Use this tool?

UserProblemHow This Helps
Automotive EngineerComparing engine specs from US (hp) and European (kW) manufacturersUses converter to standardize all power ratings.
HVAC TechnicianFurnace rated in BTU/h, but needs to match with electrical system capacity in kWConverts to ensure proper electrical supply.
Physics StudentHomework problem gives power in hp but needs answer in wattsQuick conversion checks work.
HomeownerComparing air conditioner power consumption (watts) with generator capacity (kW)Converts to ensure generator can handle the load.

💡 Pro Tips for Using this tool

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Remember that 1 kW ≈ 1.34 hp for quick mental estimates.
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For HVAC, 1 ton of cooling ≈ 12,000 BTU/h ≈ 3.5 kW.
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Use this tool to compare electric motor kW ratings with engine hp ratings.
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When dealing with very large powers (power plants), use MW for convenience.
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Bookmark this tool for quick engineering calculations.

⚠️ Common Mistakes

⚠️
Confusing 'Power' (Watts) with 'Energy' (Watt-hours); Power is the rate of doing work, while Energy is the total work done over time.
⚠️
Using 'Brake Horsepower' (BHP) and 'Wheel Horsepower' (WHP) interchangeably without accounting for drivetrain loss.
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Forgetting the distinction between thermal power and electrical power when sizing heaters or air conditioning units.

❓ Frequently Asked Questions

Yes, completely free, no signup required.
Watt (W), kilowatt (kW), megawatt (MW), mechanical horsepower (hp), metric horsepower (PS), BTU per hour (BTU/h).
1 mechanical hp = 745.7 W, 1 metric hp (PS) = 735.5 W. They are slightly different.
1 mechanical horsepower = 745.7 watts exactly.
1 BTU per hour = approximately 0.293071 watts.
1 kW = 1000 watts. Commonly used for electrical power.
No. All calculations are done locally in your browser.
Yes, the tool is responsive.
1 ton of refrigeration = 12,000 BTU/h. You can do that manually with the result.
This version focuses on common units. Boiler hp is a specialized unit.
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HandyToolsBox Team
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We build free, privacy-first online tools for designers, creators, and everyday users. All image processing happens in your browser — your files are never stored or shared.