British Thermal Unit to Gigajoule Converter

One British Thermal Unit equals 0.000001055055853 Gigajoule (1 BTU = 0.000001055055853 GJ). Multiply a British Thermal Unit value by 0.000001055055853 to get the equivalent in Gigajoule. Use the calculator above for instant results, or follow the formula, worked examples, and reference table below.

Formula

GJ = BTU × 0.000001055055853

Multiply the British Thermal Unit value by 0.000001055055853 to get the equivalent value in Gigajoule.

Example Conversions

1 British Thermal Unit (BTU)

0.000001055055853 Gigajoule (GJ)

5 British Thermal Unit (BTU)

0.000005275279263 Gigajoule (GJ)

10 British Thermal Unit (BTU)

0.00001055055853 Gigajoule (GJ)

25 British Thermal Unit (BTU)

0.00002637639632 Gigajoule (GJ)

100 British Thermal Unit (BTU)

0.0001055055853 Gigajoule (GJ)

Conversion Table

Common conversion values from British Thermal Unit to Gigajoule
British Thermal Unit (BTU) Gigajoule (GJ)
0.1 1.055056e-7
0.5 5.275279e-7
1 0.000001055055853
2 0.000002110111705
5 0.000005275279263
10 0.00001055055853
25 0.00002637639632
50 0.00005275279263
100 0.0001055055853
250 0.0002637639632
500 0.0005275279263
1000 0.001055055853

How to Convert Manually

Use these steps to convert British Thermal Unit values to Gigajoule without the calculator.

  1. Write down the value in British Thermal Unit (BTU) that you want to convert.
  2. Multiply that value by 0.000001055055853.
  3. For example, 10 British Thermal Unit × 0.000001055055853 = 0.00001055055853 Gigajoule.
  4. Label the result as Gigajoule (GJ).

Relative Size Comparison

1 British Thermal Unit
1 Gigajoule947817.1203British Thermal Units
1GJ

This chart shows the visual difference in size between exactly one British Thermal Unit and one Gigajoule.

About British Thermal Unit and Gigajoule

The British thermal unit is about 1,055.06 joules — the heat to raise one pound of water by 1 °F. US heating and cooling equipment is rated in BTU per hour. The gigajoule is one billion joules, roughly the energy in 26 liters of gasoline. District heating and industrial energy contracts bill in gigajoules. One British Thermal Unit equals 0.000001055055853 Gigajoule (1 BTU = 0.000001055055853 GJ). British Thermal Unit to Gigajoule conversion comes up most often in air conditioner and furnace ratings in the US and in US natural gas appliance specs, typically when figures need restating for district heating bills.

Precision and Rounding: Energy factors mix exact definitions (1 kWh = 3,600,000 J; 1 cal = 4.184 J thermochemical) with measured conventions (1 BTU ≈ 1,055.056 J). Nutrition and utility bills round to whole units; engineering heat calculations should keep the full factor until the final step.

Conversion factors per NIST Special Publication 811 and the BIPM SI Brochure (9th edition) (reference).

Worked Example

15 British Thermal Unit equals 0.00001582583779 Gigajoule.

15 BTU × 0.000001055055853 = 0.00001582583779 GJ

FAQ

How do I convert British Thermal Unit to Gigajoule?

Multiply the British Thermal Unit value by 0.000001055055853 to get the equivalent value in Gigajoule.

What is the formula for British Thermal Unit to Gigajoule?

The formula is GJ = BTU × 0.000001055055853.

How many Gigajoule are in 1 British Thermal Unit?

1 British Thermal Unit equals 0.000001055055853 Gigajoule.

Can I convert Gigajoule back to British Thermal Unit?

Yes. 1 Gigajoule equals 947817.1203 British Thermal Unit, and the related converter can reverse the calculation.

What are common names for British Thermal Unit and Gigajoule?

British Thermal Unit is shown as BTU and may also be searched as btu, british thermal unit. Gigajoule is shown as GJ and may also be searched as gigajoule, gigajoules.

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