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Therms to Joules Converter.

Convert US natural-gas therm energy to joules using the International Table Btu.

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Joules (J): 105,505,585.262

Joules (J)

0.0000000000

One US therm is 100,000 International Table Btu, equal to 105,505,585.262 J.

FAQs

How does the therms to joules converter work?

One US therm is 100,000 International Table Btu, equal to 105,505,585.262 J.

Use Cases

Natural Gas Energy Conversion

Convert natural gas consumption from therms to joules for scientific calculations, engineering projects, or comparing energy content across different fuel types.

Example: Convert 5 therms to joules: 5 × 105,505,585.262 = 527,527,926.31 joules.

Heating System Sizing

When designing heating systems, convert therms (as listed on utility bills) to joules to calculate heat output requirements or compare with equipment ratings in metric units.

Example: A furnace using 2 therms per hour produces about 211,011,170.5 joules per hour.

Frequently Asked Questions

What is a therm?
A therm is a unit of heat energy equal to 100,000 British thermal units (Btu). In the US, it is commonly used to measure natural gas consumption. This converter uses the International Table Btu, which is defined as exactly 1055.05585262 joules.
How many joules are in one therm?
One therm equals 100,000 International Table Btu. Since one Btu (IT) is 1055.05585262 joules, one therm equals 105,505,585.262 joules (approximately 105.5 megajoules).
Why use the International Table Btu?
The International Table (IT) Btu is a standardized definition used in engineering and science. It provides a consistent conversion factor, ensuring accurate and comparable energy values across different applications and regions.

Tips & Common Mistakes

Tips

  • Remember that 1 therm = 100,000 Btu (IT) and 1 Btu (IT) = 1055.05585262 joules, so multiply therms by 105,505,585.262 to get joules.
  • For quick estimates, you can round 1 therm to approximately 105.5 megajoules (MJ).
  • Double-check your input: the converter expects therms, not Btu or other units. If you have Btu, divide by 100,000 to get therms first.
  • Use this converter for energy content comparisons, but always refer to official standards for billing or regulatory purposes.

Common Mistakes to Avoid

  • Confusing the therm with the thermie (th), which is a different unit. This converter uses the US natural-gas therm (100,000 Btu IT).
  • Using the wrong Btu definition (e.g., the thermochemical Btu) which gives a slightly different joule value. This converter uses the International Table Btu.
  • Forgetting to multiply by 100,000 when converting from Btu to therms before using the converter.

Last updated: August 13, 2026