Horsepower to Watt Converter

Converts horsepower (hp) to watt (W) and back. The conversion factor is shown below every result.

745.699872 W

Source: NIST SP 811, Appendix B (1 hp = 745.69987158227022 W exactly)

How to Convert Horsepower to Watt

W = hp × 745.6998715823

What Is a Horsepower?

The mechanical horsepower (hp) is defined as exactly 550 foot-pounds-force per second.

What Is a Watt?

The watt (W) is the SI unit of power, equal to one joule per second.

hp = W × 0.0013410221

Common Horsepower to Watt Reference Points

Real-world reference values for quick sanity checks.

ItemHorsepower (hp)Watt (approx.)
A typical shop vacuum motor1.5 hp1,118.55 W
A small electric motor0.5 hp372.85 W
Reference values are illustrative approximations for common items, not measured specifications.

Horsepower to Watt Conversion Table

Horsepower (hp)Watt (W)
0.25 hp186.424968 W
0.5 hp372.849936 W
1 hp745.699872 W
1.5 hp1118.549807 W
2 hp1491.399743 W
5 hp3728.499358 W
10 hp7456.998716 W
25 hp18642.49679 W
Source: NIST SP 811, Appendix B (1 hp = 745.69987158227022 W exactly)

Frequently Asked Questions

How do I convert horsepower to watts?

Multiply the horsepower value by 745.6998715823. For example, 2 hp × 745.6998715823 = 1,491.4 W.

How many watts does a 1 hp motor actually draw from the wall?

A 1 hp motor's mechanical output is 745.7 W, but its electrical input is higher because no motor is 100% efficient; a typical motor might draw 900 to 1,000 W or more to deliver 745.7 W of shaft power, depending on its efficiency rating.

Is electrical horsepower the same as mechanical horsepower?

No, though they're close. Electrical horsepower is defined as exactly 746 W, a round number chosen by convention, while mechanical horsepower is 745.69987158227022 W. This page uses mechanical horsepower.

Recommended

A good measuring tool marked in both hp and W removes the guesswork at the point of use.

Cedrick Reese

Ready Utilities was founded by Cedrick Reese, a retired veteran and web developer who enjoys building free, user-friendly online tools that simplify everyday tasks. His journey began in the early 2000s with affiliate marketing and niche site development, which grew into a passion for creating practical digital utilities and calculators. After retiring, he earned a Computer Systems Technician certificate from UEI College, completed Electro-Mechanical Technologies at Tulsa Welding School, and finished the Carpentry program at Florida State College at Jacksonville. Today, he combines his technical background and craftsmanship by building furniture using traditional woodworking methods, gardening, and developing helpful online tools for users worldwide.