How to convert watts to BTU per hour
One watt equals 3.4121 BTU per hour, so multiply the number of watts by 3.4121:
BTU/h = W × 3.4121
W = BTU/h ÷ 3.4121 (1 BTU/h = 0.293071 W)
Example: 1,000 W → 1,000 × 3.4121 = 3,412.14 BTU/h.
Going the other way, divide by 3.4121, or multiply by 0.293071; the BTU per hour to watts converter does it for you.
Everyday values
| Watts | BTU per hour | For example |
|---|---|---|
| 1,000 W | 3,412.14 BTU/h | 1 kW |
| 2,640 W | 9,008.05 BTU/h | a 9,000 BTU AC's cooling |
| 3,517 W | 12,000.5 BTU/h | one ton of cooling |
| 5,000 W | 17,060.7 BTU/h | 5 kW |
When you need this conversion
One watt is 3.412 BTU/h. Converting heating or cooling capacity from kW (common outside the US) to BTU/h helps compare products sold in different markets.
Watt to BTU per hour conversion table
| W | BTU/h | W | BTU/h |
|---|---|---|---|
| 500 W | 1,706.07 BTU/h | 5,500 W | 18,766.8 BTU/h |
| 1,000 W | 3,412.14 BTU/h | 6,000 W | 20,472.8 BTU/h |
| 1,500 W | 5,118.21 BTU/h | 6,500 W | 22,178.9 BTU/h |
| 2,000 W | 6,824.28 BTU/h | 7,000 W | 23,885 BTU/h |
| 2,500 W | 8,530.35 BTU/h | 7,500 W | 25,591.1 BTU/h |
| 3,000 W | 10,236.4 BTU/h | 8,000 W | 27,297.1 BTU/h |
| 3,500 W | 11,942.5 BTU/h | 8,500 W | 29,003.2 BTU/h |
| 4,000 W | 13,648.6 BTU/h | 9,000 W | 30,709.3 BTU/h |
| 4,500 W | 15,354.6 BTU/h | 9,500 W | 32,415.3 BTU/h |
| 5,000 W | 17,060.7 BTU/h | 10,000 W | 34,121.4 BTU/h |
About the units
- Watt (W): one joule per second, the SI unit of power.
- BTU per hour (BTU/h): one International Table BTU per hour, about 0.2931 W.
Both are units of power. The conversion factor comes from the exact definitions above, so the calculator is exact; results are only rounded for display (up to six significant digits).
Frequently asked questions
How many BTU per hour are in one watt?
One watt is 3.4121 BTU per hour. One BTU per hour is 0.293071 watts.
How do I convert watts to BTU per hour?
Multiply the value in watts by 3.4121. To go back, divide by 3.4121.
What is 1,000 W in BTU per hour?
1,000 W = 3,412.14 BTU/h.
What is 2,640 W in BTU per hour?
2,640 W = 9,008.05 BTU/h.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.