Joules to BTUs Converter
Enter the energy in joules below to convert it to btus.
Convert Joules to BTUs
Enter a value in joules (J) to convert to btus (BTU).
Joule to British Thermal Unit Conversion Table
Table showing various joule measurements converted to btus. Click any preset value or arrow to load it into the converter.
| Joules (J) | BTUs (BTU) |
|---|---|
| 1 J | 0.000947817 BTU |
| 2 J | 0.0018956 BTU |
| 2.5 J | 0.0023695 BTU |
| 5 J | 0.0047391 BTU |
| 10 J | 0.0094782 BTU |
| 15 J | 0.0142173 BTU |
| 20 J | 0.0189563 BTU |
| 25 J | 0.0236954 BTU |
| 30 J | 0.0284345 BTU |
| 50 J | 0.0473909 BTU |
How to Convert Joules to BTUs
To convert joules to btus, multiply the energy by the following conversion ratio: 0.000947817 btus/joule.
Since one joule is equal to 0.000947817 btus, you can use this simple formula to convert:
The energy in btus is equal to the energy in joules multiplied by 0.000947817.
For example, here's how to convert 5 joules to btus using the formula above.
How Many BTUs Are in a Joule?
There are 0.000947817 btus in a joule, which is why we use this value in the formula above.
Our joule to british thermal unit calculator automatically converts your energy measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Joules and btus are both units used to measure energy. Keep reading to learn more about each unit.
What Is a Joule?
Coherent SI unit of energy and work (1 W·s = 1 N·m). It serves as a primary reference unit for measuring energy across scientific and practical applications. [1]
The joule is classified as an International System of Units (SI) unit of energy. Joules can be abbreviated as J; for example, 1 joule can be written as 1 J.
As the primary coherent reference unit for energy in this category, all other energy units are mathematically anchored to the joule (J).
In practice, joules (J) are widely used across standard energy applications within International System of Units (SI) workflows, engineering documentation, and technical data sheets.
What Is a British Thermal Unit?
A british thermal unit is a unit of energy equal to 1,055.0558526 joules (J), the base unit for energy. Thermal energy unit equal to 1,055.056 Joules. [2]
The british thermal unit is classified as a US customary and imperial unit of energy. BTUs can be abbreviated as BTU; for example, 1 british thermal unit can be written as 1 BTU.
When working with btus (BTU) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, btus (BTU) are widely used across large-scale industrial, bulk, and macro-level energy specifications within US customary and imperial workflows, engineering documentation, and technical data sheets.
When converting energy between joules (J) and btus (BTU), keep full floating-point precision (1 J = 0.000947817 BTU; 1 BTU = 1,055.0558526 J) during intermediate calculations and round only the final british thermal unit figure to match your instrument tolerance.
More Joule & British Thermal Unit Conversions
Need to calculate in the opposite direction? Use our btus to joules converter (BTU to J) to switch your starting unit immediately. You can also explore related tools such as converting kilowatt-hours to btus, converting joules to calories, or converting joules to kilojoules.
Frequently Asked Questions
References
- [1]NIST CODATA StandardNIST CODATA (CODATA Energy & Thermodynamic Constants)·Energy Metrology Standard — Joules (J) to BTUs (BTU)
- [2]NIST SP 811 SpecificationNIST SP 811 (NIST SP 811 App. B.9 (Energy, Work & Heat))·Unit Specifications: Joule (J) & British Thermal Unit (BTU) (BTU)
- [3]BIPM ReferenceBIPM (Derived SI Unit: Joule (J))·Conversion Factors & Mathematical Basis (J to BTU)