BTU ↔ kW Converter
Use this calculator to convert heating or cooling capacity between BTU per hour (BTU/h) and kilowatts (kW).
Reference: 1 kW = 3,412.142 BTU/h, and 1 ton cooling = 12,000 BTU/h.
What is a BTU and why convert it to kW?
A BTU (British Thermal Unit) measures heat energy. In HVAC and appliance specs, you usually see BTU/h, which means how much heat is moved or produced each hour. A kW (kilowatt) is a power unit in the metric system and is commonly used for electrical equipment ratings.
If you compare air conditioners, heat pumps, electric heaters, furnaces, or industrial equipment, you often need to convert between these two units. That is exactly what this btu kw calculator does.
BTU to kW formula
The conversion is straightforward:
- kW = BTU/h ÷ 3,412.142
- BTU/h = kW × 3,412.142
Because the relationship is fixed, conversion is always consistent and precise.
Quick examples
- 5,000 BTU/h = 1.47 kW
- 12,000 BTU/h = 3.52 kW
- 18,000 BTU/h = 5.27 kW
- 24,000 BTU/h = 7.03 kW
Common BTU/h and kW conversion table
| BTU/h | kW | Approx. Cooling Tons |
|---|---|---|
| 6,000 | 1.76 | 0.50 |
| 9,000 | 2.64 | 0.75 |
| 12,000 | 3.52 | 1.00 |
| 18,000 | 5.27 | 1.50 |
| 24,000 | 7.03 | 2.00 |
| 36,000 | 10.55 | 3.00 |
| 48,000 | 14.07 | 4.00 |
| 60,000 | 17.58 | 5.00 |
When this conversion is useful
1) Comparing HVAC units from different markets
Some manufacturers publish capacity in BTU/h, while others use kW. Conversion lets you compare like-for-like before buying.
2) Interpreting energy modeling reports
Engineering, energy audit, and building simulation reports often use SI units (kW). If your equipment labels are in BTU/h, you need both.
3) Planning electrical infrastructure
Understanding thermal load in kW helps when coordinating panel sizing, backup power strategy, and operating cost analysis.
Important note: capacity vs electrical consumption
BTU/h and kW conversion gives you thermal capacity equivalence. It does not automatically tell you the electric power draw of an HVAC system. Real electrical consumption depends on efficiency ratings such as SEER, EER, and COP.
- A 12,000 BTU/h system has 3.52 kW of thermal capacity.
- Its electric consumption may be much lower than 3.52 kW if the system is efficient.
Tips for more accurate planning
- Use local climate data for realistic heating/cooling loads.
- Account for insulation quality, windows, occupancy, and ventilation.
- Use professional load calculation methods (like Manual J) for home HVAC sizing.
- Separate thermal load conversion from electrical usage estimates.
FAQ
Is 12,000 BTU/h always 1 ton?
Yes. In HVAC terminology, 1 refrigeration ton is defined as 12,000 BTU/h.
How many BTU/h are in 1 kW?
Exactly 3,412.142 BTU/h per kW.
Can I use this for heating and cooling?
Yes. The unit conversion itself is identical for either application.
Does this calculator estimate electricity bills?
No. It converts thermal capacity units only. For bill estimates, include efficiency and runtime data.
Bottom line
This btu kw calculator makes it easy to switch between two common power/capacity units used in HVAC, engineering, and energy analysis. Enter either BTU/h or kW, click the relevant conversion button, and get instant results you can use for comparisons and planning.