Kilocalories to Joules
Convert kilocalories to joules instantly. 1 kcal = 4,184 J. Includes the exact factor, a conversion table of common values and the definition of both units.
How to convert kilocalories to joules
To convert kilocalories to joules, multiply by 4,184. The relationship is fixed, so the same factor works for any quantity — there is nothing to look up and nothing that changes with temperature, location or context.
J = kcal × 4,184
Kilocalories to Joules conversion table
The values people look up most often, rounded for reading. Use the calculator above for anything in between.
| Kilocalories | Joules |
|---|---|
| 1 kcal | 4,184 J |
| 2 kcal | 8,368 J |
| 3 kcal | 12,552 J |
| 5 kcal | 20,920 J |
| 10 kcal | 41,840 J |
| 20 kcal | 83,680 J |
| 25 kcal | 104,600 J |
| 50 kcal | 209,200 J |
| 100 kcal | 418,400 J |
| 500 kcal | 2,092,000 J |
| 1,000 kcal | 4,184,000 J |
What is a kilocalory?
The food Calorie, equal to a thousand small calories.
What is a joule?
The SI unit of energy: one newton-metre, or one watt for one second.
The formula
J = kcal × 4,184
Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.
How to use the Kilocalories to Joules
- Type the number of kilocalories you want to convert.
- Read the result in joules straight away — there is no button to press.
- Check the table below for the values that come up most often, or reverse the conversion with the linked joules to kilocalories page.
Kilocalories to Joules — frequently asked questions
How many joules are in a kilocalory?
One kilocalory equals 4,184 J. J = kcal × 4,184
What is the formula to convert kilocalories to joules?
The formula is J = kcal × 4,184. It is an exact definition rather than an approximation, so the conversion never drifts no matter how large the number.
How do I convert joules back to kilocalories?
Divide instead of multiplying: one joule is 0.0002390057 kcal. The reverse converter is linked in the related tools list.
Is this conversion exact?
Yes. Both units are defined against the same base unit by international agreement, so the factor is exact — any rounding you see is only in the display, which you can widen by entering more decimal places.
Is this kilocalories to joules free to use?
Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.
What people search for
This page answers each of these searches. They are the exact phrases visitors use to find the kilocalories to joules.
- kilocalories to joules
- 1 kilocalory to joules
- how many joules in a kilocalory
- kcal2j
- kilocalories in joules
- kilocalories to joules converter
- convert kilocalories to joules
About this calculator
Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.
Last reviewed August 19, 2026 · Calculation runs client-side · No data collected · Report an error