Convert therms to joules

1 thm=105,505,585.3J

Use the converter below to change any therms value into joules instantly — with formula, conversion table, and real-world examples.

You have

Equals

105,505,585.3

Conversion formula

Forward

joules = therms × 105,505,585.3

Reverse

therms = joules × 9.4782e-9

Example: 10 thm × 105,505,585.3 = 1,055,055,853 J.

About both units

From

Therm

thm

The therm equals 100,000 BTU or 105.5 megajoules. Used in US and UK natural-gas billing. A typical UK home uses 200–500 therms per year for heating.

Real-world: UK home heating: 200–500 therms/year. 1 therm = about $1.50 US (2024) or £1.00 UK.

Read full therm reference →

Joule

The joule is the SI unit of energy, work and heat. Defined as one newton-metre or one watt-second. Named after James Prescott Joule who demonstrated the mechanical equivalent of heat. Lifting a 100 g apple 1 metre requires about 1 J.

Real-world: Lifting a 100 g apple 1 m: ≈ 1 J. 100 kcal snack: 418,400 J. Hand grenade: ~650 kJ.

Read full joule reference →

Therm to Joule conversion table

Common therms to joules values for quick reference.

Therm (thm)	Joule (J)
1 thm	105,505,585.3 J
10 thm	1,055,055,853 J
100 thm	10,550,558,530 J
500 thm	52,752,792,650 J
1,000 thm	105,505,585,300 J
5,000 thm	527,527,926,500 J
10,000 thm	1,055,055,853,000 J
50,000 thm	5,275,279,265,000 J
100,000 thm	10,550,558,530,000 J
500,000 thm	52,752,792,650,000 J

Tips & common mistakes

Quick tips

1 therm = 100,000 BTU = 105.5 MJ = 29.3 kWh.
UK bills often quote both therms and kWh.
In metric-dominant EU, gas is billed in kWh or m³.

Avoid these

Comparing therms and kWh without conversion on a mixed-unit bill.
Assuming therms are used globally — only US and UK.
Using BTU when bill shows therms — factor of 100,000.

Frequently asked questions

How many joules in a therm?

One therm equals 105,505,585.3 joules.

How do I convert therms to joules?

Multiply the therm value by 105,505,585.3 to get the equivalent in joules.

What is 100 therms in joules?

100 therms equals 10,550,558,530 joules.

Is a therm bigger than a joule?

Yes. 1 therm equals 105,505,585.3 joules, so one therm is larger.

How to convert therms to joules without a calculator?

Multiply by 105,505,585.3 for a quick estimate; use a calculator for precise results.

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