Btu to hp Converter
Engines are rated in horsepower, while heat is rated in Btu per hour. Divide Btu/h by 2,544.43 to switch.
Quick answer: multiply the result in Btu/h by 0.00039301. For example, 10,000 Btu/h is 3.93 hp, 2,544.4336 Btu/h is 1 hp and 5,000 Btu/h is 1.965 hp.
The Btu/h to hp formula
One mechanical horsepower is about 2,544 Btu per hour (Wikipedia: British thermal unit).
So divide the Btu/h by 2,544.43 to get horsepower.
Take 10,000 Btu/h. Multiply by 0.00039301. The answer is 3.93 hp.
Take 2,544.4336 Btu/h. Multiply by 0.00039301. The answer is 1 hp.
Btu per hour to horsepower
Btu/h means British thermal units per hour, a rate of heat flow.
hp here means the mechanical horsepower of about 745.7 W (Wikipedia: Horsepower).
The factor 0.00039301 joins the two.
How to convert Btu/h to hp step by step
- Write down the result in Btu/h.
- Multiply it by 0.00039301.
- The answer is in hp.
- Check it against the chart above.
Example 1: 10,000 Btu/h
- Start with 10,000 Btu/h.
- 10,000 × 0.00039301 = 3.93.
- The result is 3.93 hp.
10,000 Btu/h = 3.93 hp
Example 2: 2,544.4336 Btu/h
- Start with 2,544.4336 Btu/h.
- 2,544.4336 × 0.00039301 = 1.
- The result is 1 hp.
2,544.4336 Btu/h = 1 hp
Example 3: 5,000 Btu/h
- Start with 5,000 Btu/h.
- 5,000 × 0.00039301 = 1.965.
- The result is 1.965 hp.
5,000 Btu/h = 1.965 hp
Metric horsepower is a little smaller, at about 735.5 W (Wikipedia: Horsepower).
Btu/h to hp conversion table
| Btu/h | hp | W |
|---|---|---|
| 10,000 Btu/h | 3.93 hp | 2,930.71 W |
| 2,544.4336 Btu/h | 1 hp | 745.7 W |
| 5,000 Btu/h | 1.965 hp | 1,465.36 W |
| 25,000 Btu/h | 9.825 hp | 7,326.78 W |
| 1,000 Btu/h | 0.393 hp | 293.07 W |
| 50,000 Btu/h | 19.651 hp | 14,653.55 W |
| 100,000 Btu/h | 39.301 hp | 29,307.1 W |
The highlighted row, 10,000 Btu/h, is the default of the converter. The last column gives W.
A quick mental shortcut for Btu/h to hp
Divide the Btu/h by 2,500.
So 10,000 Btu/h is about 3.9 hp.
What Btu/h measures
Btu/h means British thermal units per hour, a rate of heat flow.
It is used mainly in North America (Wikipedia: British thermal unit).
What hp measures
hp here means the mechanical horsepower of about 745.7 W (Wikipedia: Horsepower).
It is also 550 foot-pounds of force per second.
Worked example: 25,000 Btu/h
25,000 Btu/h times the factor gives 9.8254 hp.
Check it by dividing 9.8254 by the factor, which returns 25,000.
Worked example: 5,000 Btu/h
5,000 Btu/h times the factor gives 1.9651 hp.
Check it by dividing 1.9651 by the factor, which returns 5,000.
The size of one horsepower
A mechanical horsepower is 745.7 W (Wikipedia: Horsepower).
That is about 2,544 Btu per hour.
A motor example
A motor that gives 5 hp makes about 12,722 Btu/h of work.
Real motors also lose some heat.
A large load
A load of 50,000 Btu/h is about 19.651 hp.
That is about 14.7 kW.
Going the other way
To go back, multiply the hp by 2,544.43.
So 3.93 hp is about 10,000 Btu/h.
Check your answer
Your answer should be smaller than your starting number.
Reverse the sum and you should get your first number back.
More worked values
15,000 Btu/h is 5.8952 hp, 1,000 Btu/h is 0.39302 hp and 50,000 Btu/h is 19.651 hp.
A heater and a motor
A heater that gives 20,000 Btu/h is about 7.8603 hp of heat flow. That does not mean a motor of that size would run it.
Heat and shaft power share a unit, but they are different things.
Checking your result
Multiply the hp by 2,544.43. 5.8952 hp times 2,544.43 gives back 15,000 Btu/h.
More values at a glance
2,000 Btu/h is 0.78603 hp, 8,000 Btu/h is 3.1441 hp and 30,000 Btu/h is 11.79 hp.
75,000 Btu/h is 29.476 hp, and 150,000 Btu/h is 58.952 hp.
The unit sizes
One horsepower is about 2,544.43 Btu per hour. Heat ratings in Btu/h are therefore large numbers.
If a result looks very large or very small, compare it with these sizes before you use it.
Quick conversion answers
| Conversion | Result |
|---|---|
| 10,000 Btu/h | 3.93 hp |
| 2,544.4336 Btu/h | 1 hp |
| 5,000 Btu/h | 1.965 hp |
| 25,000 Btu/h | 9.825 hp |
| 1,000 Btu/h | 0.393 hp |
| 50,000 Btu/h | 19.651 hp |
Round numbers for Btu/h and hp
Use these round numbers to check your own answer. 50,000 Btu/h is 19.65 hp, 500,000 Btu/h is 196.5 hp and 5,000,000 Btu/h is 1,965 hp.
Going the other way, 5 hp is 12,720 Btu/h, 50 hp is 127,200 Btu/h and 500 hp is 1,272,000 Btu/h.
A round trip with Btu/h
Say you start with 370,000 Btu/h. It becomes 145.4 hp. Divide that by the factor and you land on 370,000 Btu/h again.
Now start from 250 hp instead. It becomes 636,100 Btu/h, and multiplying by the factor returns 250 hp.
More Btu/h values
A rate of 1,000 Btu/h is 0.39301 hp, 20,000 Btu/h is 7.8602 hp and 50,000 Btu/h is 19.651 hp.
Going back, 1 hp is 2,544.43 Btu/h.
These values use the mechanical horsepower.
Where this conversion is used
Heating and cooling gear is rated in Btu.
Motors and engines are rated in horsepower.
Common mistakes to avoid
- Mixing up the direction. Going from Btu/h to hp should make the number smaller.
- Using metric horsepower. This page uses the mechanical horsepower of about 745.7 W.
- Mixing Btu and Btu/h. A Btu is energy, while Btu/h is power. This page needs Btu per hour.
- Rounding too early. The answer for 5,000 Btu/h is 1.965 hp. Cut it to 2 hp and you are off by about 1.8 percent, and the gap grows if you reuse it.
Related converters
Example: 1,000 Btu/h
1,000 Btu/h times the factor gives 0.39301 hp.
Check it by dividing 0.39301 by the factor, which returns 1,000.
Example: 50,000 Btu/h
50,000 Btu/h times the factor gives 19.651 hp.
Check it by dividing 19.651 by the factor, which returns 50,000.
Frequently asked questions
How do I convert Btu/h to hp?
divide by 2,544.43.
How many hp is 10,000 Btu/h?
3.9301 hp.
How many hp is 2,544.4 Btu/h?
1 hp.
How many Btu/h is 1 hp?
About 2,544.4 Btu/h.
How many hp is 10 Btu/h?
0.0039301 hp.
How many hp is 100 Btu/h?
0.039301 hp.
Sources
- Wikipedia: British thermal unit (en.wikipedia.org)
- Wikipedia: Horsepower (en.wikipedia.org)
