Authoritative definitions of the International System of Units and SI prefixes.
Dedicated unit pair
Mechanical horsepower to Watts
Convert hp to W instantly, then review the formula, assumptions, and rounding guidance.
Energy, work, heat & powerInstant result
Decimals
Formula result = input × 745.699871582 ÷ 1. 1 hp = 745.6999 W
Common examples
One value, several units
Watts745.6999 W
Kilowatts0.7457 kW
Megawatts0.0007 MW
Metric horsepower1.0139 PS
BTU per hour2,544.4336 BTU/h
Conversion table
| hp | W |
|---|---|
| 1 hp | 745.6999 W |
| 2 hp | 1,491.3997 W |
| 5 hp | 3,728.4994 W |
| 10 hp | 7,456.9987 W |
| 25 hp | 18,642.4968 W |
| 50 hp | 37,284.9936 W |
| 100 hp | 74,569.9872 W |
Conversion chart
1 hp745.6999 W
5 hp3,728.4994 W
10 hp7,456.9987 W
25 hp18,642.4968 W
50 hp37,284.9936 W
Worked example
1 mechanical horsepower is approximately 745.7 watts.
Unit definition
Mechanical horsepower (hp) One mechanical horsepower equals 745.699871582 watt.
Unit history
Mechanical horsepower is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert hp to watt.
3. Convert the base value to W and apply your display precision.
Understand the result before using it
Mechanical horsepower to Watts converts a value measured in Mechanical horsepower (hp) into the equivalent value in Watts (W). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = input × 745.699871582 ÷ 1
Assumptions
- Mechanical horsepower and Watts represent the same power quantity.
- The input is expressed in hp; the output is expressed in W.
- The unit definitions and conventional relationship shown on this page apply.
Worked example
1 hp = 745.699871582 W. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a hp measurement in a document that expects W.
- Compare a mechanical horsepower value with a value reported in watts.
- Check the hp-to-W arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Do not confuse hp with another unit that has a similar name or symbol.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Mechanical horsepower to Watts?
result = input × 745.699871582 ÷ 1 Using the displayed relationship, 1 hp equals 745.699871582 W.
How many Watts are in one Mechanical horsepower?
One Mechanical horsepower is 745.699871582 Watts. The displayed digits may be rounded.
Can I reverse the hp to W conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts W back to hp.
Is the Mechanical horsepower to Watts result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.