18 Btu to Joules

18 Btu ≈ 18991 J

Calculation: J = 18 Btu × 1055.06 ≈ 18991 J

Btu to Joule Converter

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How to Convert Btu to Joule

1 Btu = 1055.06 Joules

Joule = Btu × 1055.06

Example: 18 Btu × 1055.06 = 18991 J

Reverse Conversion

To convert Joules back to Btu:

  • Remember, 1 joule equals 0.000947817 Btu.
  • To convert 18991 J to Btu, multiply 18991 x 0.000947817, resulting in 18 Btu.

18 Btu is also equal to:

  • 18.991 kilojoule
  • 0.0052753 kilowatt hour
  • 4.539 calorie (nutritional)
  • 5.2753 watt hour
About these units

Btu: British thermal unit (IT) — legacy heat unit based on heating water.

Joule: SI unit of energy: 1 J = 1 N·m = 1 kg·m²·s⁻².

Frequently Asked Questions

How much is 18 Btu in Joules?

18 Btu equals 18991 Joules. This is calculated by multiplying 18 by the conversion factor 1055.06.

What does 18 Btu look like in Joules?

18 Btu (18991 Joules) is the heat from a candle burning for a few minutes.

How do you calculate 18 Btu to Joules?

Multiply 18 by the conversion factor 1055.06. The calculation is 18 × 1055.06 = 18991 Joules. This factor is defined by international measurement standards.

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18 Btu = 18991 Joules
18 Btu = 18991 Joules — conversion chart

Nearby Conversions

8 Btu8440 Joules 9 Btu9496 Joules 10 Btu10550 Joules 11 Btu11610 Joules 12 Btu12660 Joules 13 Btu13720 Joules 14 Btu14770 Joules 15 Btu15830 Joules 16 Btu16880 Joules 17 Btu17940 Joules 19 Btu20050 Joules 20 Btu21100 Joules 21 Btu22160 Joules 22 Btu23210 Joules 23 Btu24270 Joules 24 Btu25320 Joules 25 Btu26380 Joules 26 Btu27430 Joules 27 Btu28490 Joules 28 Btu29540 Joules

For general conversions between Btu and Joules, see the Btu to Joules converter.

Also convert Btu to:

Conversion factors verified against NIST, BIPM, ISO 80000-4 1 cal_IT = 4.1868 J by definition (BIPM/ITS-90). Last reviewed: April 2026
Adilson Fernandes By Adilson Fernandes
Tiago Fernandes Reviewed by Tiago Fernandes

All unit conversions on CoolConversion use conversion factors defined or documented by internationally recognised standards bodies (such as ISO and NIST), including both SI and non-SI units.