2 Rydberg to Kilojoule
Quick answer
2 Rydberg (Ry) equals
4.359744e-21 kJ
To convert 2 Rydbergs to Kilojoules, multiply by 2.179872e-21. Therefore, 2 Rydberg (Ry) equals 4.359744e-21 Kilojoule (kJ).
Formula: kJ = Ry × 2.179872e-21. Calculation: 2 × 2.179872e-21 = 4.359744e-21 kJ.
Convert Rydberg (Ry) to Kilojoule (kJ) online with our free unit converter. In energy, 1 Ry = 2.179872e-21 kJ. Explore step-by-step conversion steps, mathematical formulas, and quick conversion reference tables below.
Worked example: converting Rydberg to Kilojoule
- Step 1 — start with the formula. kJ = Ry × 2.179872e-21
- Step 2 — substitute your figure. 2 Ry × 2.179872e-21
- Step 3 — read the result. 2 Ry = 4.359744e-21 kJ
- Step 4 — check it in reverse. Ry = kJ × 4.587425e+20 returns 2 Ry, which matches the figure you started with.
Energy Converter
27 units available
2 Ry = 4.359744e-21 kJ
Formula:
kJ = Ry × 2.179872e-21With your value: 2 Ry = 4.359744e-21 kJ
How big is that?
Everyday references on a logarithmic scale, all expressed in rydberg so you can sanity-check the result.
Other Rydberg to Kilojoule conversions
Rydberg to Kilojoule Conversion Table
| Rydberg (Ry) | Kilojoule (kJ) |
|---|---|
| 0.5 | 1.089936e-21 |
| 1 | 2.179872e-21 |
| 2 | 4.359744e-21 |
| 5 | 1.089936e-20 |
| 10 | 2.179872e-20 |
| 15 | 3.269808e-20 |
| 20 | 4.359744e-20 |
| 25 | 5.449680e-20 |
| 50 | 1.089936e-19 |
| 100 | 2.179872e-19 |
| 250 | 5.449680e-19 |
| 500 | 1.089936e-18 |
| 1000 | 2.179872e-18 |
Kilojoule to Rydberg Conversion Table
| Kilojoule (kJ) | Rydberg (Ry) |
|---|---|
| 0.5 | 2.293713e+20 |
| 1 | 4.587425e+20 |
| 2 | 9.174851e+20 |
| 5 | 2.293713e+21 |
| 10 | 4.587425e+21 |
| 15 | 6.881138e+21 |
| 20 | 9.174851e+21 |
| 25 | 1.146856e+22 |
| 50 | 2.293713e+22 |
| 100 | 4.587425e+22 |
| 250 | 1.146856e+23 |
| 500 | 2.293713e+23 |
| 1000 | 4.587425e+23 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
Rydberg (Ry)
Energy
Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
Kilojoule (kJ)
Energy
Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
How to Convert Rydberg to Kilojoule
To convert from Rydberg (Ry) to Kilojoule (kJ), multiply the value by 2.179872e-21.
Formula: kJ = Ry × 2.179872e-21
Reverse: Ry = kJ × 4.587425e+20
Step-by-Step Example
- Start with your value in Rydberg. For example: 5 Ry
- Multiply by the conversion factor: 5 x 2.179872e-21
- The result is: 1.089936e-20 kJ
Rydberg and Kilojoule Relationship
This calculation facilitates standardized conversion between recognized units of energy. Since 1 Rydberg represents a fraction of a Kilojoule (1 Kilojoule ≈ 4.587e+20 Rydbergs), the Kilojoule is the larger measurement interval. Understanding the relationship between Rydberg and Kilojoule is essential for accurate calculations in physics, engineering, commerce, and daily applications.
About Rydberg
The Rydberg (symbol: Ry) is a recognized unit in the Standard measurement framework, utilized within energy applications for precision and standardized data representation.
Common uses of Rydberg: energy calculations, engineering and science, education.
About Kilojoule
The Kilojoule (symbol: kJ) is a recognized unit in the Metric (SI) measurement framework, utilized within energy applications for precision and standardized data representation.
Common uses of Kilojoule: energy calculations, engineering and science, education.
Frequently Asked Questions
- What is 2 Rydberg in Kilojoule?
- 2 Rydberg equals 4.359744e-21 Kilojoule.
- How many Kilojoules are in 1 Rydberg?
- There are exactly 2.179872e-21 Kilojoules in 1 Rydberg. This means the conversion factor from Rydberg to Kilojoule is 2.179872e-21.
- What is the formula to convert Rydberg to Kilojoule?
- The formula to convert Rydberg to Kilojoule is: kJ = Ry × 2.179872e-21. For example, to convert 10 Rydbergs to Kilojoules, you would multiply 10 by 2.179872e-21.
- What is a Rydberg?
- The Rydberg (symbol: Ry) is a recognized unit in the Standard measurement framework, utilized within energy applications for precision and standardized data representation.
- What is a Kilojoule?
- The Kilojoule (symbol: kJ) is a recognized unit in the Metric (SI) measurement framework, utilized within energy applications for precision and standardized data representation.
- What are the common uses of Rydberg?
- The Rydberg is commonly used in energy calculations, engineering and science, education.
Related Energy Conversions
Cite this page
UnitConvertLab. (2026). 2 Rydberg to Kilojoule. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/2-rydberg-to-kilojoule