Mechanical horsepower.
Horsepowers to BTU per hour Converter — hp to BTU/h
Convert Horsepower (hp) to BTU per hour (BTU/h) using the exact conversion factor (1 horsepower = 2,544.433578 btu per hour). See the formula, worked examples, conversion table, history, and common uses.
Horsepowers to BTU per hour converter
Converter
Power Converter
Convert watts, horsepower, refrigeration tons, BTU per hour, and engineering power units.
Context values
Some unit families need one extra value for a physically accurate result.
Power rate using BTU per hour.
Result = input x 745.6998716 / 0.2930710702.
Power uses the watt as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Horsepowers to BTU per hour
Horsepower and BTU per hour both describe power output, and the conversion is a routine part of comparing an engine or motor's spec sheet across countries that use different power units. Horsepower is most often used for us and uk vehicle engine power ratings.
Formula
btu per hour = horsepowers × 2544.43357764
This factor comes from each unit's defined relationship to the category's base unit: 1 horsepower equals 745.699871582 base units, and 1 btu per hour equals 0.293071070172 base units, so dividing one by the other gives the direct horsepower-to-btu per hour factor of 2544.43357764.
Simple example
1 hp × 2544.433578 = 2,544.433578 BTU/h
1 horsepower = 2,544.433578 btu per hour.
Real-world example
100 hp × 2544.433578 = 254,443.3578 BTU/h
100 horsepowers = 254,443.3578 btu per hour.
Conversion table
| Horsepower (hp) | BTU per hour (BTU/h) |
|---|---|
| 1 hp | 2,544.433578 BTU/h |
| 10 hp | 25,444.33578 BTU/h |
| 100 hp | 254,443.3578 BTU/h |
| 500 hp | 1,272,216.789 BTU/h |
| 1,000 hp | 2,544,433.578 BTU/h |
| 5,000 hp | 12,722,167.89 BTU/h |
Reverse conversion: BTU per hour to Horsepower
1 BTU/h × 0.0003930147789 = 0.0003930148 hp
1 btu per hour = 0.0003930148 horsepowers.
horsepowers = btu per hour × 0.000393014778922
For a page dedicated to this direction, see BTU per hour to Horsepower.
Understanding the Horsepower
Horsepower (hp) measures power. Mechanical horsepower is defined as exactly 745.6998715822702 watts. It is classified as a US/imperial customary unit.
Where it's used: United States and United Kingdom (vehicle and engine specifications)
Mechanical horsepower vs. metric horsepower. Mechanical horsepower (745.7 W) and metric horsepower/PS (735.5 W) differ by about 1.4% — a US car spec sheet in 'hp' and a European one in 'PS' are not directly comparable numbers without conversion.
Uses of the Horsepower today
- US and UK vehicle engine power ratings
- Motor and engine specifications in English-speaking markets
History of the Horsepower
James Watt popularized horsepower in the 1780s as a marketing figure, comparing his steam engines' output to the working capacity of a horse (based on his estimate of a horse turning a mill), so buyers could grasp engine capability in familiar terms. The unit stuck long after its origin as a sales tool, eventually being formally defined at exactly 550 foot-pounds per second.
Historical origin. Horsepower was not the invention of a single named person; it developed through the process described above.
Understanding the BTU per hour (BTU/h)
Power rate using BTU per hour.
Horsepower — sources
- NIST Special Publication 811 — Documents the exact watt-equivalence of mechanical horsepower.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many btu per hour are in 1 horsepower?
1 horsepower equals 2,544.433578 btu per hour, using the exact defined conversion factor rather than an estimate.
How do I convert horsepower to btu per hour?
Multiply the horsepower value by 2544.433578. The converter above does this instantly to whatever precision you set.
How do I convert btu per hour back to horsepower?
Use the reverse factor: 1 btu per hour equals 0.0003930148 horsepowers. You can also use the swap control in the converter above to flip the direction instantly.
What is a horsepower?
Horsepower (hp) measures power. Mechanical horsepower is defined as exactly 745.6998715822702 watts. It is classified as a US/imperial customary unit.
What is a btu per hour?
BTU per hour (BTU/h) is a unit of power.
Is the horsepower to btu per hour conversion exact?
Yes. Mechanical horsepower is defined as exactly 745.6998715822702 watts. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between mechanical horsepower vs. metric horsepower?
Mechanical horsepower (745.7 W) and metric horsepower/PS (735.5 W) differ by about 1.4% — a US car spec sheet in 'hp' and a European one in 'PS' are not directly comparable numbers without conversion.
Where is the horsepower still used today?
United States and United Kingdom (vehicle and engine specifications)