Kilojoule to Joule Converter
Energy · unit-converter
Convert Kilojoule to Joule with fixed input and output units, a step-by-step formula line, and reference tables. Factors are joule-based; food energy uses thermochemical calories. The full Energy Converter also includes MMBtu, toe, thermal kWh, and MeV/GeV.
Calculator
From: Kilojoule (kj)
To: Joule (j)
About Kilojoule
One kilojoule is 1,000 J. Scientific and engineering contexts often use kJ alongside joules.
About Joule
The joule is the SI unit of energy. All other units here are converted through fixed joule equivalents.
How to convert kilojoules to joules
1 kilojoule is equal to 1000 joule when both are expressed in joule-equivalents:
1 kj = (1,000 J ÷ 1 J) j = 1000 j
SI prefix: 1 kJ = 1,000 J.
Each kilojoule is defined as 1,000 J and each joule as 1 J in this tool, so one kj equals 1,000 ÷ 1 j = 1000 j.
Let d(kj) be the numeric amount in Kilojoule (kj), and d(j) the amount in Joule (j). Then:
d(j) = d(kj) × (1,000 / 1)
Equivalently, divide by how many kj fit into one j (joules per j divided by joules per kj):
d(j) = d(kj) ÷ 0.001
Or: joule = kilojoule ÷ 0.001
Examples
Example #1: Convert 1 kj to joule
1 kj = 1 kj × (1,000/1) j = 1000 j
1 kj = 1 kj ÷ 0.001 = 1000 j
Example #2: Convert 10 kj to joule
10 kj = 10 kj × (1,000/1) j = 10000 j
10 kj = 10 kj ÷ 0.001 = 10000 j
Summary
To convert Kilojoule to Joule, multiply the value in kj by the ratio of joules per kj divided by joules per j. Equivalently: value_j = value_kj × (1000 / 1). Numerically, 1 kj equals 1000 j.
Relationship context
Both units are SI energy (joules). Conversions use fixed joule factors, so results stay consistent with the definitions in this converter. The factor from Kilojoule to Joule is 1.000000e+3 (1 kj = 1000 j).
Conversion tables
| Kilojoule (kj) | Joule (j) |
|---|---|
| 0.1 | 100 |
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 4 | 4,000 |
| 5 | 5,000 |
| 6 | 6,000 |
| 7 | 7,000 |
| 8 | 8,000 |
| 9 | 9,000 |
| Kilojoule (kj) | Joule (j) |
|---|---|
| 10 | 10,000 |
| 20 | 20,000 |
| 30 | 30,000 |
| 40 | 40,000 |
| 50 | 50,000 |
| 60 | 60,000 |
| 70 | 70,000 |
| 80 | 80,000 |
| 90 | 90,000 |
| 100 | 100,000 |