Reference conversions
| Source unit | Equivalent |
|---|---|
| 1 calorie | 4.184 J |
| 1 kilocalorie | 4,184 J |
| 1 watt-hour | 3,600 J |
| 1 BTU | 1,055.05585262 J |
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Energy and Heat Converter
Convert common energy and heat units through joules. The calculator uses the thermochemical calorie and a fixed BTU conversion factor.
Worked example
1,000 J = 239.00573614 cal = 0.27777778 Wh.
Important interpretation
“Calorie” can mean a small calorie or a food kilocalorie. Confirm the unit label before copying a nutrition or laboratory value.
Related converters
Usage boundaries and result checks
Heat Converter is for this task: Convert joules, calories, kilocalories, BTU, watt-hours, and kilowatt-hours. It runs in the browser; start with a short, non-sensitive sample and confirm the behavior before processing more data.
Best use
Use it for a focused Heat Converter task when a quick browser workbench is appropriate.
Input
numbers, units, and the options shown by the calculator
Output
the calculated or converted values described on the page
Before reuse
For Heat Converter: Confirm units, precision, rounding, and formula scope. Use an authoritative workflow for engineering or financial decisions. See the test method.