Joule to British Thermal Unit

Free instant joule to british thermal unit converter. 1 J = 0.000947817 BTU.

0.000947817
Formula
1 J = 0.000947817 BTU

Common Joule to British Thermal Unit values

Joule (J)British Thermal Unit (BTU)
10.000947817
50.00473909
100.00947817
250.0236954
500.0473909
1000.0947817
5000.473909
10000.947817

How does Joule to British Thermal Unit conversion work?

Type a value in the Joule (J) field and the equivalent in British Thermal Unit (BTU) appears instantly to the right. The math uses the exact formula shown above — no rounding errors, no approximations beyond standard floating-point precision. Use the swap button to flip the units and see the inverse conversion.

Joule. The SI unit of energy. About the energy of a small apple falling from waist height.

British Thermal Unit. The energy needed to raise 1 pound of water by 1°F. Common in heating/cooling system ratings.

⚡ Instant results

No submit button — the result updates as you type. Math runs entirely in your browser, so it’s as fast as your device.

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Works in any modern browser — Mac, Windows, Linux, iPhone, Android, tablets. No installation, no signup.

🎯 Accurate conversions

Conversion factors come from the official standard (NIST, BIPM, ISO definitions where applicable). Values are precise to standard floating-point limits.

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Free, every time. No account, no email, no “trial” that becomes paid. Ad-supported so you never have to pay.

Frequently asked

What is the formula for converting Joule to British Thermal Unit?+
The formula is: 1 J = 0.000947817 BTU. Type any value into the calculator above and the result appears instantly.
How do I convert British Thermal Unit back to Joule?+
Click the swap button (⇄) above to go to the British Thermal Unit → Joule converter, or use the inverse formula derived from the one shown.

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