Kilocalories to Joules Converter
kcal → J · ⚡ Energy
1 Kilocalories = 4,184 Joules
How to convert Kilocalories to Joules
To convert Kilocalories to Joules, multiply the value in Kilocalories by 4,184. For example, 5 kcal = 20,920 J.
Going from Kilocalories to Joules means applying a fixed conversion factor: one Kilocalories (kcal) is exactly 4,184 Joules (J). Type any number into the converter above and the equivalent updates instantly, or use the reference table for quick lookups.
Energy conversions appear in nutrition, fitness, physics, utility bills, and engineering. The same quantity of energy can be expressed in joules, calories, kilowatt-hours, or BTU depending on the context.
Understanding Kilocalories and Joules
The joule is the SI unit, but everyday contexts use others: food labels use kilocalories (often just called 'calories'), electricity bills use kilowatt-hours, and heating and cooling systems use BTU (British Thermal Units). One food calorie is actually a kilocalorie — 1,000 of the small physics calories — which is a frequent source of confusion.
How accurate is this conversion?
Energy conversions use standard definitions: 1 calorie = 4.184 joules, 1 kilowatt-hour = 3,600,000 joules, 1 BTU = 1,055.06 joules. These are internationally agreed values, making the conversions exact.
All conversion factors on ClearUnits are based on internationally recognised standards (the International System of Units, SI, and official definitions). Factors are reviewed for accuracy and the calculator uses full-precision values, rounding only the displayed result.
Quick reference: common Kilocalories to Joules values
The most frequently searched conversions are 1 Kilocalories = 4,184 Joules, 5 Kilocalories = 20,920 Joules, 10 Kilocalories = 41,840 Joules, and 100 Kilocalories = 418,400 Joules. The full table further down covers every common value, and the calculator handles any number you need in between.
Pro tip: When comparing appliance efficiency or heating costs, convert everything to kilowatt-hours first, since that's the unit your utility bill uses — it makes the real-world cost immediately comparable.
Kilocalories to Joules — Conversion Table
| Kilocalories (kcal) | Joules (J) |
|---|---|
| 0.1 kcal | 418.4 J |
| 0.25 kcal | 1,046 J |
| 0.5 kcal | 2,092 J |
| 1 kcal | 4,184 J |
| 2 kcal | 8,368 J |
| 5 kcal | 20,920 J |
| 10 kcal | 41,840 J |
| 25 kcal | 104,600 J |
| 50 kcal | 209,200 J |
| 100 kcal | 418,400 J |
| 250 kcal | 1,046,000 J |
| 500 kcal | 2,092,000 J |
| 1000 kcal | 4,184,000 J |