21 Joules to Kilojoules
Convert 21 joules (J) to kilojoules (kJ) with formulas, examples, and conversion tables.
J
kJ
21 J = 0.021 kJ
Full precision:0.021 kJ
Step-by-Step Solution
To convert 21 joules to kilojoules, we divide by 1000 because one kilojoule equals exactly 1000 joules.
1 kilojoule = 1000 joules
Since there are 1000 joules in every kilojoule, we divide our value by this factor:
21 ÷ 1000 = 0.021 kilojoules
So 21 joules = 0.021 kilojoules.
Quick check: 0.021 × 1000 = 21 joules
Joules to Kilojoules Conversion Table
| Joules | Kilojoules |
|---|---|
| 1 J | 0.001 kJ |
| 2 J | 0.002 kJ |
| 3 J | 0.003 kJ |
| 4 J | 0.004 kJ |
| 5 J | 0.005 kJ |
| 10 J | 0.01 kJ |
| 20 J | 0.02 kJ |
| 21 J | 0.021 kJ |
| 50 J | 0.05 kJ |
| 100 J | 0.1 kJ |
21 Joules in Other Units
| Unit | 21 J = |
|---|---|
| Joules to Kilojoules | 0.021 kJ |
| Joules to Megajoules | 0.000021 MJ |
| Joules to Gigajoules | 2.1e-8 GJ |
| Joules to Watt-hours | 0.0058333 Wh |
| Joules to Kilowatt-hours | 0.00000583 kWh |
| Joules to Megawatt-hours | 5.8333e-9 MWh |
| Joules to Calories | 5.0191 cal |
| Joules to Kilocalories | 0.0050191 kcal |
| Joules to BTU | 0.019904 BTU |
| Joules to Therms | 1.9904e-7 therm |
| Joules to Foot-pounds | 15.4888 ft·lb |
| Joules to Electronvolts | 1.3107e+20 eV |
| Joules to Ergs | 210000000 erg |