How do you convert BTU/hr to watts?

To convert BTU per hour to watts, multiply the BTU/hr value by 0.29307107. For example, 10,000 BTU/hr × 0.29307107 ≈ 2,931 W.

What is the difference between BTU/hr and watts?

BTU/hr is a unit of power based on heat energy in the imperial system, while the watt is the SI unit of power. Both measure energy per unit time; they just use different base units. They can be converted exactly using 1 BTU/hr = 0.29307107 W.

BTU to Watts Converter (BTU/hr ⇄ W)

Q: How many watts is 1 BTU per hour?

1 BTU per hour is approximately 0.29307107 watts. A quick rule of thumb is 1 BTU/hr ≈ 0.293 W.

Q: How many BTU/hr is 1 kW?

1 kilowatt is approximately 3,412 BTU per hour (more precisely 3,412.14163 BTU/hr).

Q: How many watts is 12,000 BTU?

12,000 BTU/hr is about 3,516 watts (12,000 × 0.29307107 ≈ 3,516.9 W). This is roughly 3.5 kW and corresponds to 1 ton of cooling.

How to convert BTU to watts

BTU per hour (BTU/hr) and watts (W) are both units of power. BTU/hr is common in HVAC and heating, while watts are the standard SI unit used for electrical and mechanical power.

Exact conversion (BTU_IT):

1 BTU/hr = 0.29307107 W
1 W = 3.41214163 BTU/hr

Formulas:

Watts from BTU/hr:

\( P_{W} = P_{\text{BTU/hr}} \times 0.29307107 \)

BTU/hr from watts:

\( P_{\text{BTU/hr}} = P_{W} \times 3.41214163 \)

Step-by-step example: 12,000 BTU/hr to watts

Start with the power in BTU/hr: 12,000 BTU/hr.
Multiply by the factor 0.29307107 W per BTU/hr.
\( 12{,}000 \times 0.29307107 \approx 3{,}516.9 \text{ W} \)

So a 12,000 BTU/hr air conditioner is roughly a 3.5 kW unit and is commonly called a 1-ton AC.

Quick reference table (BTU/hr to watts)

BTU/hr	Watts (approx.)	kW	Tons of cooling
5,000	1,465 W	1.47 kW	0.42 ton
8,000	2,345 W	2.35 kW	0.67 ton
10,000	2,931 W	2.93 kW	0.83 ton
12,000	3,517 W	3.52 kW	1.0 ton
18,000	5,275 W	5.28 kW	1.5 tons
24,000	7,034 W	7.03 kW	2.0 tons

BTU/hr vs watts: what\u2019s the difference?

Both BTU/hr and watts measure power (energy per unit time), but they come from different systems:

BTU/hr is based on the British Thermal Unit (imperial/US customary).
Watt (W) is the SI unit of power (1 W = 1 joule per second).

HVAC equipment in North America is usually rated in BTU/hr or tons, while electrical systems, generators, and solar panels are rated in watts or kilowatts. Converting between them lets you compare thermal load to electrical capacity.

Common use cases

Checking if a generator or inverter can run a given air conditioner or heater.
Comparing AC units specified in BTU/hr with heat pumps specified in kW.
Estimating how much electrical power a heating or cooling load will require.

BTU standards used in this calculator

This tool supports two common BTU definitions:

BTU (IT) \u2013 International Table BTU, widely used in HVAC: 1 BTU = 1055.056 J.
BTU (thermochemical) \u2013 slightly different definition: 1 BTU = 1054.350 J.

For most practical HVAC and appliance calculations, BTU (IT) is appropriate and the difference between the two is less than 0.1%.

BTU to watts conversion FAQ

How many watts is 1 BTU per hour?

1 BTU/hr \u2248 0.29307107 W. A quick mental approximation is 0.293 W.

How many BTU/hr is 1 kW?

1 kW = 1,000 W. Using 1 W = 3.41214163 BTU/hr:

\( 1{,}000 \times 3.41214163 \approx 3{,}412 \text{ BTU/hr} \)

How many watts is 12,000 BTU?

12,000 BTU/hr \u2248 3,517 W or about 3.5 kW. This is the typical rating for a 1-ton air conditioner.

Does BTU/hr equal input electrical watts?

Not exactly. BTU/hr is usually the thermal output (cooling or heating capacity), while watts on the nameplate can be electrical input. The ratio between them is the efficiency (EER, SEER, COP, etc.). This converter only handles the unit conversion; it does not account for efficiency losses.