Convert BTU to kilojoules
1 BTU = 1.055056 kJ. Change the amount below, or read the formula and the reference table further down.
1 BTU equals
kilojoules
1 BTU = 1.055056 kJ
The formula
BTU and kilojoules both measure energy from the same zero, so a single multiplier does the job.
kJ = BTU × 1.05505585
Going the other way? Convert kilojoules to BTU.
BTU to kilojoules table
Common values, rounded for reading.
| BTU (BTU) | Kilojoules (kJ) |
|---|---|
| 1 | 1.0551 |
| 2 | 2.1101 |
| 3 | 3.1652 |
| 4 | 4.2202 |
| 5 | 5.2753 |
| 6 | 6.3303 |
| 7 | 7.3854 |
| 8 | 8.4404 |
| 9 | 9.4955 |
| 10 | 10.5506 |
| 15 | 15.8258 |
| 20 | 21.1011 |
| 25 | 26.3764 |
| 30 | 31.6517 |
| 40 | 42.2022 |
| 50 | 52.7528 |
| 75 | 79.1292 |
| 100 | 105.51 |
| 250 | 263.76 |
| 500 | 527.53 |
| 1,000 | 1,055.06 |
Questions people ask
- How many kilojoules are in a BTU?
- One BTU equals 1.05505585 kilojoules.
- How do I convert BTU to kilojoules by hand?
- Multiply the number of BTU by 1.05505585. For a rough check, 1.1 is close enough for most everyday use.
- What is 1 BTU in kilojoules?
- 1 BTU is 1.055056 kilojoules.
Calcuit generates this page from a unit table, so the factors here match every other page on the site.