How many calories in a joule?

1 calorie equals approximately 4.184 joules. 1 kilocalorie (food calorie) equals 4,184 joules or 4.184 kilojoules.

What is a kilowatt-hour?

A kilowatt-hour (kWh) is the energy consumed by a 1,000-watt appliance running for 1 hour. It equals 3.6 million joules. This is what your electricity meter measures.

How do I convert BTU to joules?

1 BTU (British Thermal Unit) equals approximately 1,055 joules. Multiply BTUs by 1,055 to get joules.

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Free Energy Converter — Joules, Calories, kWh, BTU

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From

0.000239

1 J = 0.000239 kcal

Quick Reference

Value	Equivalent
1 kJ	0.239006 kcal / 0.000278 kWh
1 kcal	4186.8 J / 4.1868 kJ
1 kWh	3,600,000 J / 3600 kJ / 859.845 kcal
1 BTU	1055.06 J / 0.252164 kcal
1 eV	1.60218×10⁻¹⁹ J

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About Energy Conversion

Energy is measured in many units depending on the context. Joules (J) are the SI standard, calories are used in nutrition, kilowatt-hours measure electricity consumption, and BTUs are common in heating/cooling. Understanding these conversions helps with electricity bills, diet planning, and engineering calculations.

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