power unit

Horsepower

Everything important about a horsepower: definition, symbol, exact relationships, scale, common uses, mistakes, FAQ, and converter links.

Horsepower is a power unit with the symbol hp. 1 hp = 745.699871582 W It belongs to the power system used across Xunits converter pages.

Quick facts

Unit name
Horsepower
Plural
horsepower
Symbol
hp
Quantity
power
Category
Power
Base relationship
1 hp = 745.699871582 W
Base unit
Watt (W)
Converter hub
Power converter

Scale comparison

This chart places hp beside neighboring power units by their relationship to W.

W1 W is the base reference for this Xunits power category.
kW1 kW = 1,000 W
MW1 MW = 1,000,000 W
hp1 hp = 745.699871582 W
BTU/h1 BTU/h = 0.293071070172 W

Definition and symbol

The horsepower is written with the symbol hp. In professional writing, keep the number and symbol together, preserve capitalization, and avoid replacing the symbol with a similar-looking informal abbreviation unless the source uses it.

1 hp = 745.699871582 W

Scale and relationships

Horsepower is best understood relative to nearby power units. Power measures the rate at which energy is transferred or work is done. The SI unit is the watt, equal to one joule per second. The table below shows the exact Xunits relationship used by converter pages.

UnitSymbolRelationship
WattW1 W is the base reference for this Xunits power category.
KilowattkW1 kW = 1,000 W
MegawattMW1 MW = 1,000,000 W
Horsepowerhp1 hp = 745.699871582 W
BTU per HourBTU/h1 BTU/h = 0.293071070172 W

Where horsepower is used

Power units appear in motors, engines, pumps, compressors, generators, appliances, HVAC equipment, electrical systems, and energy analysis. Horsepower is especially useful when the source instrument, document, product listing, or regional convention uses hp as its native unit.

Common mistakes

FAQ

What is a horsepower?

Horsepower is a power unit represented by hp. 1 hp = 745.699871582 W

How do I convert horsepower to another unit?

Use a matching Xunits converter page, or convert through the base relationship shown above. For most professional work, keep the original value visible and round only the final answer.

What is the most common mistake with hp?

The most common mistake is treating the numeric value as self-explanatory. Always keep the unit symbol and context with the number.