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Category: Converters

Energy Converter

System ideaMissing a tool?

Convert joules, calories, watt-hours, BTU and more

Convert between joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours and British thermal units using fixed, published ratios.

Result23.900574

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What this tool does

Each energy unit is defined as a fixed ratio to one joule, using the thermochemical calorie (4.184 J) and the International Table BTU (1,055.05585262 J). A conversion is a single multiplication and division, so results need no network lookup.

How to use it

  1. Enter an energy value.
  2. Choose the unit you're converting from and to.
  3. The converted value appears immediately.

Privacy

This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.

Frequently asked questions

How many joules are in a kilocalorie?
One kilocalorie (food calorie) equals 4,184 joules, using the thermochemical calorie definition applied by this converter.
How many watt-hours are in a BTU?
One BTU equals about 0.293071 watt-hours, derived from the International Table BTU of 1,055.05585262 joules.

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