Energy Converter
Convert between joules, calories, kilocalories, watt-hours, kilowatt-hours, and BTU.
Energy is measured differently depending on the field — joules in physics, calories and kilocalories in nutrition (a food label's "calories" are actually kilocalories), kilowatt-hours on an electricity bill, and BTU in heating specifications — and converting between them is necessary whenever information crosses from one domain into another, like estimating an appliance's electricity cost from its wattage.
This converter covers all the common energy units with precise conversion factors, useful for understanding a food's energy content in joules, converting a heater's BTU rating into kilowatt-hours to estimate running cost, or working between scientific and everyday energy units.
How to use Energy Converter
- 1
Enter your value
Type the energy value you want to convert.
- 2
Select the source unit
Choose the unit your value is currently in.
- 3
Select the target unit
Choose the unit you want to convert to.
- 4
Read the result
The converted value updates instantly.
Features
- Covers joules, calories, kilocalories, watt-hours, kilowatt-hours, and BTU
- Precise conversion factors across scientific and everyday units
- Instant live conversion
Frequently asked questions
Common mistakes to avoid
- Confusing nutritional Calories (kilocalories) with scientific calories, understating food energy content by a factor of 1,000.
- Mixing up energy (joules, kWh — a total amount) with power (watts — a rate) when reading appliance specifications.
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