Watts to BTU per Hour Converter
Convert watts to BTU per hour — one watt is 3.412 BTU/h. Results update as you type; exact factors shown.
One watt is 3.4121 BTU per hour — see the exact factor, not a rounded rule of thumb.
How the watts to btu per hour converter works
Power converts through the watt. Mechanical horsepower is 550 ft·lbf/s = 745.6999 W; metric horsepower (PS, used in European car specs) is 735.4988 W. Air-conditioner capacities are quoted in kW, BTU/h (1 W = 3.412 BTU/h) or tons of refrigeration (3.517 kW).
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common power conversions
| From | To | Units |
|---|---|---|
| 100 W | 341.2142 BTU/h | watts to BTU per hour |
| 250 W | 853.0354 BTU/h | watts to BTU per hour |
| 500 W | 1,706.0708 BTU/h | watts to BTU per hour |
| 1,000 W | 3,412.1416 BTU/h | watts to BTU per hour |
| 1,500 W | 5,118.2125 BTU/h | watts to BTU per hour |
| 2,000 W | 6,824.2833 BTU/h | watts to BTU per hour |
| 2,500 W | 8,530.3541 BTU/h | watts to BTU per hour |
| 3,000 W | 10,236.4249 BTU/h | watts to BTU per hour |
| 5,000 W | 17,060.7082 BTU/h | watts to BTU per hour |
| 7,500 W | 25,591.0623 BTU/h | watts to BTU per hour |
| 10,000 W | 34,121.4164 BTU/h | watts to BTU per hour |
| 20,000 W | 68,242.8327 BTU/h | watts to BTU per hour |
Units in this converter and their exact factors
| Unit | Symbol | One unit in watts |
|---|---|---|
| watt | W | 1 watt |
| kilowatt | kW | 1,000 watt |
| megawatt | MW | 1,000,000 watt |
| horsepower (mechanical) | hp | 745.6998715823 watt |
| metric horsepower (PS) | PS | 735.49875 watt |
| BTU per hour | BTU/h | 0.29307107 watt |
| ton of refrigeration | TR | 3,516.8528421 watt |
FAQFrequently asked questions about power conversion
How many BTU/h is 1 watt?
3.412 BTU/h.
What is a 2,000 W heater in BTU/h?
6,824 BTU/h.
Why convert?
Heating appliances are rated in watts in metric markets and BTU/h in the US, so comparing them needs one unit.
Is a 1,500 W heater the same everywhere?
The power is, yes — 5,118 BTU/h. What differs is only the label.
What does a person emit?
About 100 W at rest, or 341 BTU/h — which is why a full room heats up.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.