Convert BTU/hr, watts, kW and horsepower to find equivalent heating or power output in any supported unit, including W and hp, instantly.

BTU Per Hour Calculator

Enter exactly one value to calculate the other two

BTU Per Hour Formula

The calculator converts between BTU per hour, watts, kilowatts, and mechanical horsepower. It uses watts as the base unit, then converts the result to the other units.

BTU / hr = W * 3.412141633
W = BTU / hr / 3.412141633
hp = W / 745.6998715822702
W = hp * 745.6998715822702
kW = W / 1000
W = kW * 1000
  • BTU/hr = British thermal units per hour, a unit commonly used for heat output or cooling capacity
  • W = watts
  • kW = kilowatts
  • hp = mechanical horsepower
  • 3.412141633 = BTU/hr per watt
  • 745.6998715822702 = watts per mechanical horsepower

If you enter BTU/hr, the calculator first converts BTU/hr to watts, then uses watts to find horsepower. If you enter watts or kilowatts, it converts the value to base watts, then calculates BTU/hr and horsepower. If you enter horsepower, it converts horsepower to watts, then calculates BTU/hr.

Common BTU/hr, Watt, and Horsepower Conversions

Use these values as quick reference points when checking a result.

Watts Kilowatts BTU/hr Horsepower
100 W 0.1 kW 341.2142 BTU/hr 0.134102 hp
500 W 0.5 kW 1,706.0708 BTU/hr 0.670511 hp
1,000 W 1 kW 3,412.1416 BTU/hr 1.341022 hp
2,000 W 2 kW 6,824.2833 BTU/hr 2.682044 hp
5,000 W 5 kW 17,060.7082 BTU/hr 6.705110 hp

Typical Uses for BTU/hr Ratings

Rating Type Common Unit What It Usually Describes
Air conditioner capacity BTU/hr How much heat the unit can remove per hour
Electric heater output W, kW, or BTU/hr How quickly electrical power is converted to heat
Engine or motor power hp or W Mechanical power output, not necessarily heat output

Example Calculations

Example 1: Convert 1,500 watts to BTU/hr and horsepower

Given:

  • W = 1,500

Convert watts to BTU/hr:

BTU / hr = 1500 * 3.412141633 = 5118.2124

Convert watts to horsepower:

hp = 1500 / 745.6998715822702 = 2.0115

So, 1,500 W is about 5,118.2124 BTU/hr and 2.0115 hp.

Example 2: Convert 12,000 BTU/hr to watts and horsepower

Given:

  • BTU/hr = 12,000

Convert BTU/hr to watts:

W = 12000 / 3.412141633 = 3516.8528

Convert watts to horsepower:

hp = 3516.8528 / 745.6998715822702 = 4.7162

So, 12,000 BTU/hr is about 3,516.8528 W, or 3.5169 kW, and 4.7162 hp.

FAQ

What is BTU per hour?

BTU per hour, written as BTU/hr, is a rate of heat transfer. One BTU is the amount of heat needed to raise one pound of water by about 1 degree Fahrenheit. BTU/hr tells you how many BTUs are added or removed in one hour.

How many BTU/hr are in 1 watt?

1 watt equals 3.412141633 BTU/hr. For a quick estimate, you can use 1 W ≈ 3.412 BTU/hr.

Is horsepower the same as BTU/hr?

No. Horsepower is a unit of power, often used for mechanical output. BTU/hr is also a power rate, but it is commonly used for heating and cooling. They can be converted through watts, but the practical meaning depends on the system. For example, motor horsepower is not always the same as heat delivered to a room because efficiency and losses may matter.