BTUs to Kilojoules (BTU → kJ) — Free Online Converter

BTU → kJ Reference Table

BTU	kJ
0.001 BTU	0.001055055853 kJ
0.002 BTU	0.002110111705 kJ
0.003 BTU	0.003165167558 kJ
0.004 BTU	0.00422022341 kJ
0.005 BTU	0.005275279263 kJ
0.006 BTU	0.006330335116 kJ
0.007 BTU	0.007385390968 kJ
0.008 BTU	0.008440446821 kJ
0.009 BTU	0.009495502674 kJ
0.01 BTU	0.01055055853 kJ
0.02 BTU	0.02110111705 kJ
0.03 BTU	0.03165167558 kJ
0.04 BTU	0.0422022341 kJ
0.05 BTU	0.05275279263 kJ
0.06 BTU	0.06330335116 kJ
0.07 BTU	0.07385390968 kJ
0.08 BTU	0.08440446821 kJ
0.09 BTU	0.09495502674 kJ
0.1 BTU	0.1055055853 kJ
0.2 BTU	0.2110111705 kJ
0.3 BTU	0.3165167558 kJ
0.4 BTU	0.422022341 kJ
0.5 BTU	0.5275279263 kJ
0.6 BTU	0.6330335116 kJ
0.7 BTU	0.7385390968 kJ
0.8 BTU	0.8440446821 kJ
0.9 BTU	0.9495502674 kJ
1 BTU	1.055055853 kJ
1.5 BTU	1.582583779 kJ
2 BTU	2.110111705 kJ
2.5 BTU	2.637639632 kJ
3 BTU	3.165167558 kJ
3.5 BTU	3.692695484 kJ
4 BTU	4.22022341 kJ
4.5 BTU	4.747751337 kJ
5 BTU	5.275279263 kJ
5.5 BTU	5.802807189 kJ
6 BTU	6.330335116 kJ
6.5 BTU	6.857863042 kJ
7 BTU	7.385390968 kJ
7.5 BTU	7.912918895 kJ
8 BTU	8.440446821 kJ
8.5 BTU	8.967974747 kJ
9 BTU	9.495502674 kJ
9.5 BTU	10.0230306 kJ
10 BTU	10.55055853 kJ
11 BTU	11.60561438 kJ
12 BTU	12.66067023 kJ
13 BTU	13.71572608 kJ
14 BTU	14.77078194 kJ
15 BTU	15.82583779 kJ
16 BTU	16.88089364 kJ
17 BTU	17.93594949 kJ
18 BTU	18.99100535 kJ
19 BTU	20.0460612 kJ
20 BTU	21.10111705 kJ
25 BTU	26.37639632 kJ
30 BTU	31.65167558 kJ
35 BTU	36.92695484 kJ
40 BTU	42.2022341 kJ
45 BTU	47.47751337 kJ
50 BTU	52.75279263 kJ
55 BTU	58.02807189 kJ
60 BTU	63.30335116 kJ
65 BTU	68.57863042 kJ
70 BTU	73.85390968 kJ
75 BTU	79.12918895 kJ
80 BTU	84.40446821 kJ
85 BTU	89.67974747 kJ
90 BTU	94.95502674 kJ
95 BTU	100.230306 kJ
100 BTU	105.5055853 kJ
120 BTU	126.6067023 kJ
125 BTU	131.8819816 kJ
130 BTU	137.1572608 kJ
140 BTU	147.7078194 kJ
150 BTU	158.2583779 kJ
160 BTU	168.8089364 kJ
175 BTU	184.6347742 kJ
180 BTU	189.9100535 kJ
200 BTU	211.0111705 kJ
225 BTU	237.3875668 kJ
250 BTU	263.7639632 kJ
275 BTU	290.1403595 kJ
300 BTU	316.5167558 kJ
350 BTU	369.2695484 kJ
400 BTU	422.022341 kJ
450 BTU	474.7751337 kJ
500 BTU	527.5279263 kJ
600 BTU	633.0335116 kJ
700 BTU	738.5390968 kJ
750 BTU	791.2918895 kJ
800 BTU	844.0446821 kJ
900 BTU	949.5502674 kJ
1000 BTU	1055.055853 kJ
1200 BTU	1266.067023 kJ
1250 BTU	1318.819816 kJ
1500 BTU	1582.583779 kJ
1750 BTU	1846.347742 kJ
2000 BTU	2110.111705 kJ
2500 BTU	2637.639632 kJ
3000 BTU	3165.167558 kJ
4000 BTU	4220.22341 kJ
4500 BTU	4747.751337 kJ
5000 BTU	5275.279263 kJ
6000 BTU	6330.335116 kJ
7000 BTU	7385.390968 kJ
7500 BTU	7912.918895 kJ
8000 BTU	8440.446821 kJ
9000 BTU	9495.502674 kJ
10000 BTU	10550.55853 kJ
15000 BTU	15825.83779 kJ
20000 BTU	21101.11705 kJ
25000 BTU	26376.39632 kJ
50000 BTU	52752.79263 kJ
75000 BTU	79129.18895 kJ
100000 BTU	105505.5853 kJ

Values based on NIST SP 811 conversion factors

Why Convert BTUs to Kilojoules?

Converting between btus (BTU) and kilojoules (kJ) is one of the most common energy conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert BTU to kJ saves time and prevents errors.

Energy conversions from BTU to kJ are crucial for dietitians, physicists, and engineers. In nutrition, understanding the link between calories and joules helps individuals manage their diet and energy intake effectively. In the power sector, converting between kilowatt-hours and British Thermal Units (BTU) is necessary for sizing heating and cooling systems for homes and offices. Physicists rely on precise energy unit conversions to calculate work, heat, and thermodynamic processes. Whether tracking fitness goals or analyzing home energy bills, accurate conversion empowers users to make better health and financial decisions.

How to Convert BTUs to Kilojoules

To convert btus to kilojoules, use the following formula:

kJ = BTU × 1.055055853

Example: 1 BTU = 1.055055853 kJ

For example, 5 BTU = 5.275279263 kJ, 10 BTU = 10.55055853 kJ, and 100 BTU = 105.5055853 kJ. For larger values, 1000 BTU = 1055.055853 kJ. Conversely, 1 kJ = 0.9478171203 BTU. Our calculator above performs this conversion instantly with full precision — no rounding errors.

Common Mistakes to Avoid

Calorie confusion: Food 'Calories' are actually kilocalories (kcal).
Joule scale: 1 kWh is 3.6 million Joules (orders of magnitude difference).
Power vs Energy: mixing up Watts (power) and Watt-hours (energy).

Pro Tips

Food labels: Learn to read kcal; average adult needs ~2000 kcal/day.
Battery capacity: Wh = V * Ah. Useful for comparing different voltage batteries.
Efficiency: Energy cannot be created/destroyed, only converted (with some loss as heat).

What is a BTU?

British Thermal Unit. Heat to raise 1 lb of water by 1°F.

Standard in the US for HVAC systems.

What is a Kilojoule?

A unit of energy equal to 1,000 Joules.

Standard unit for food energy labeling in most of the world.

Frequently Asked Questions

How many kilojoules are in 1 btu?

1 BTU equals 1.055055853 kJ. This is an exact conversion factor defined by NIST.

How do I convert btus to kilojoules?

Multiply the value in BTU by the conversion factor. For example, 10 BTU = 10.55055853 kJ. Use our calculator above for instant results.

Is the btus to kilojoules conversion exact?

Yes, this conversion is mathematically exact based on the international definition of these units (NIST SP 811).

Can I convert btus to kilojoules offline?

Yes! OmniConvert runs entirely in your browser — no internet connection needed after the page loads. Your data never leaves your device, ensuring complete privacy.

What is the difference between btus and kilojoules?

BTUs (BTU) and Kilojoules (kJ) are both units of energy but belong to different measurement systems. 1 BTU = 1.055055853 kJ. Use the converter above to switch between them instantly.

BTUs → Kilojoules