Convert Electronvolts to Kilojoules
Instantly convert Electronvolts (eV) to Kilojoules (kJ) with our free online calculator.
Formula: eV to kJ — multiply by 1.6022e-22
Reference Table
| Electronvolts (eV) | Kilojoules (kJ) |
|---|---|
| 1 | 1.602177e-22 |
| 5 | 8.010883e-22 |
| 10 | 1.602177e-21 |
| 25 | 4.005442e-21 |
| 50 | 8.010883e-21 |
| 100 | 1.602177e-20 |
How to Convert Electronvolts to Kilojoules
Formula
To convert Electronvolts (eV) to Kilojoules (kJ): multiply by 1.6022e-22
Step-by-Step
- Start with your value in Electronvolts (eV).
- Multiply by 1.6022e-22 to perform the conversion.
- The result is your value expressed in Kilojoules (kJ).
Conversion Factor
1 eV = 1.602177e-22 kJ
Reverse Factor
1 kJ = 6.241509e+21 eV
Worked Example
Convert 25 Electronvolts to Kilojoules: 25 eV = 4.005442e-21 kJ
About Electronvolt (eV)
A unit of energy equal to the kinetic energy gained by an electron accelerating through an electric potential difference of one volt in vacuum, defined since the 2019 SI redefinition as exactly 1.602176634 × 10⁻¹⁹ joules (CODATA 2018, BIPM SI Brochure). The electronvolt is the natural working unit of atomic, molecular, and particle physics where joules are too large to be convenient: chemical bond energies are a few eV (C-C bond ~3.6 eV, O-H bond ~4.8 eV), photon energies in the visible spectrum are 1.6-3.1 eV (red to violet), X-rays carry keV (medical diagnostic ~80-140 keV, hard X-ray ~10-100 keV), nuclear-reaction Q-values are MeV (fission of U-235 releases ~200 MeV per atom), particle-collider beam energies are GeV-TeV (LHC operates at 13.6 TeV center-of-mass), and astrophysical sources reach PeV / EeV (highest-energy cosmic rays ~3 × 10²⁰ eV = 300 EeV). Particle physics papers in Physical Review D, JHEP, Nature Physics, and the PDG Review of Particle Physics report all energies, masses (E = mc² gives a free conversion), and cross-sections in eV or its derivatives. 1 eV ≈ 1.602 × 10⁻¹⁹ J ≈ 1.602 × 10⁻¹² erg.
About Kilojoule (kJ)
A metric unit of energy equal to exactly 1,000 joules. Kilojoules are the working unit for food-energy labelling outside the United States — Australia and New Zealand display kJ-only nutrition panels per FSANZ standards 1.2.7 / 1.2.8, the European Union requires kJ alongside kcal per EU Regulation 1169/2011, and Codex Alimentarius (the international food labelling standard) uses kJ. Reference values: a Big Mac is ~2,220 kJ, an adult daily energy intake is 8,000-10,500 kJ (about 2,000-2,500 kcal) per WHO/FAO Recommended Dietary Allowances, a 350 mL soft drink ~600 kJ. The kJ is also the natural engineering unit for small-scale mechanical work (joules per stroke on a punch press), small-cell battery capacity (e.g., a smartphone Li-ion at ~40 kJ), and small-scale thermodynamic calculations like an espresso machine's per-shot energy budget (~20 kJ). 1 kJ = 0.2389 kcal = 0.948 BTU = 277.8 mWh.
Quick Facts
- 1 Electronvolt equals 1.602177e-22 Kilojoules
- 1 Kilojoule equals 6.241509e+21 Electronvolts
- Electronvolt is a unit of energy
- Kilojoule is a unit of energy
- This conversion is commonly used in nutrition, electrical billing, physics, and mechanical engineering
- The Kilojoule belongs to the metric system
Common Electronvolt to Kilojoule Conversions
| Electronvolts (eV) | Kilojoules (kJ) |
|---|---|
| 0.01 | 1.602177e-24 |
| 0.1 | 1.602177e-23 |
| 0.25 | 4.005442e-23 |
| 0.5 | 8.010883e-23 |
| 1 | 1.602177e-22 |
| 2 | 3.204353e-22 |
| 3 | 4.806530e-22 |
| 5 | 8.010883e-22 |
| 10 | 1.602177e-21 |
| 15 | 2.403265e-21 |
| 20 | 3.204353e-21 |
| 25 | 4.005442e-21 |
| 50 | 8.010883e-21 |
| 75 | 1.201632e-20 |
| 100 | 1.602177e-20 |
| 250 | 4.005442e-20 |
| 500 | 8.010883e-20 |
| 1000 | 1.602177e-19 |
| 5000 | 8.010883e-19 |
| 10000 | 1.602177e-18 |
Understanding Electronvolts
The Electronvolt (symbol: eV) is a unit of energy. A unit of energy equal to the kinetic energy gained by an electron accelerating through an electric potential difference of one volt in vacuum, defined since the 2019 SI redefinition as exactly 1.602176634 × 10⁻¹⁹ joules (CODATA 2018, BIPM SI Brochure). The electronvolt is the natural working unit of atomic, molecular, and particle physics where joules are too large to be convenient: chemical bond energies are a few eV (C-C bond ~3.6 eV, O-H bond ~4.8 eV), photon energies in the visible spectrum are 1.6-3.1 eV (red to violet), X-rays carry keV (medical diagnostic ~80-140 keV, hard X-ray ~10-100 keV), nuclear-reaction Q-values are MeV (fission of U-235 releases ~200 MeV per atom), particle-collider beam energies are GeV-TeV (LHC operates at 13.6 TeV center-of-mass), and astrophysical sources reach PeV / EeV (highest-energy cosmic rays ~3 × 10²⁰ eV = 300 EeV). Particle physics papers in Physical Review D, JHEP, Nature Physics, and the PDG Review of Particle Physics report all energies, masses (E = mc² gives a free conversion), and cross-sections in eV or its derivatives. 1 eV ≈ 1.602 × 10⁻¹⁹ J ≈ 1.602 × 10⁻¹² erg.
Electronvolts are commonly used in nutrition, electrical billing, physics, and mechanical engineering.
Understanding Kilojoules
The Kilojoule (symbol: kJ) is a unit of energy. A metric unit of energy equal to exactly 1,000 joules. Kilojoules are the working unit for food-energy labelling outside the United States — Australia and New Zealand display kJ-only nutrition panels per FSANZ standards 1.2.7 / 1.2.8, the European Union requires kJ alongside kcal per EU Regulation 1169/2011, and Codex Alimentarius (the international food labelling standard) uses kJ. Reference values: a Big Mac is ~2,220 kJ, an adult daily energy intake is 8,000-10,500 kJ (about 2,000-2,500 kcal) per WHO/FAO Recommended Dietary Allowances, a 350 mL soft drink ~600 kJ. The kJ is also the natural engineering unit for small-scale mechanical work (joules per stroke on a punch press), small-cell battery capacity (e.g., a smartphone Li-ion at ~40 kJ), and small-scale thermodynamic calculations like an espresso machine's per-shot energy budget (~20 kJ). 1 kJ = 0.2389 kcal = 0.948 BTU = 277.8 mWh.
It belongs to the metric measurement system.
Kilojoules are commonly used in nutrition, electrical billing, physics, and mechanical engineering.
Why Convert Electronvolts to Kilojoules?
Converting energy between Electronvolts and Kilojoules is common in physics, nutrition, and engineering. Electricity bills use kilowatt-hours, food labels list calories or kilojoules, and mechanical engineers work with joules and BTUs. Reliable conversion helps professionals and consumers compare energy values across different contexts.
Frequently Asked Questions
How do I convert Electronvolts to Kilojoules?
A unit of energy equal to the kinetic energy gained by an electron accelerating through an electric potential difference of one volt in vacuum, defined since the 2019 SI redefinition as exactly 1. To convert Electronvolts to Kilojoules, multiply by 1.6022e-22. For example, 25 eV equals 4.005442e-21 kJ.
How many Kilojoules are in 1 Electronvolt?
There are 1.602177e-22 Kilojoules in 1 Electronvolt.
How many Electronvolts are in 1 Kilojoule?
There are 6.241509e+21 Electronvolts in 1 Kilojoule.
What is the formula for Electronvolt to Kilojoule conversion?
The formula is: multiply by 1.6022e-22. This means 1 eV = 1.602177e-22 kJ.
Is a Electronvolt bigger than a Kilojoule?
Yes. One Electronvolt is larger than one Kilojoule because 1 eV equals 1.602177e-22 kJ, which is less than 1.
When do you need to convert between Electronvolts and Kilojoules?
A metric unit of energy equal to exactly 1,000 joules. Electronvolt and Kilojoule are both energy units, so conversion comes up whenever one source of information uses one unit and another uses the other — a classic cross-reference challenge in engineering, trade, travel, and everyday life.