eV to Joules Calculator — Instant Electron Volt to Joule Conversion
Free eV to J calculator built for American physics students and engineers. Convert electron volts to joules in seconds — photon energy, semiconductor band gaps, and homework problems handled with lab-grade accuracy.
US Energy Converter - Joules, BTUs, kWh & CaloriesThe quick answer for 1 Electron Volts — type any value below for the exact result
Electron Volts
Joules
eV to J Conversion Formula
To convert electron volts to joules, multiply the eV value by 1.60218e-19. One electron volt is the kinetic energy a single electron picks up crossing a one-volt potential, and its joule equivalent sits way down at the atomic scale — 1 eV = 1.60218e-19 J.
Electron Volts and Joules Explained
Electron Volts (ev)
The electron volt (eV) is the kinetic energy a single electron gains when accelerated through an electric potential of one volt, equal to 1.60218e-19 joules. It is the working unit of atomic physics because natural energies there are small integers: chemical bonds run 1-10 eV, visible photons 1.6-3.3 eV, and diagnostic X-rays tens of keV. Its multiples scale smoothly up to the TeV beam energies of the Large Hadron Collider.
Where it is used: Standard in atomic and particle physics, photon and spectroscopy tables, semiconductor band-gap data, X-ray and radiation dosimetry contexts, and accelerator engineering.
Origin: Introduced in the early 20th century as vacuum-tube experiments made electron energies directly measurable by applied voltage; the name stuck because voltage was the observable.
Joules (j)
The joule (J) is the SI unit of energy — one newton-meter, or one watt-second — and the unit every physical equation expects after dimensional analysis. A single joule is enormous on the atomic scale: it equals about 6.2415e18 eV, or the energy of more than three quintillion red photons. Physicists convert eV to J (factor 1.60218e-19) whenever microscopic quantities must enter macroscopic formulas involving mass, velocity, power, or temperature.
Where it is used: Mandatory in SI-based publication, engineering computation, and any calculation mixing atomic quantities with everyday units like watts or kilograms.
Origin: Named for James Prescott Joule, who established the equivalence of heat and mechanical work in the 1840s; the joule anchors the modern SI energy framework.
Electron Volts to Joules Conversion Table
| Electron Volts (ev) | Joules (j) |
|---|---|
| 1 ev | 1.602180e-19 j |
| 2 ev | 3.204360e-19 j |
| 5 ev | 8.010900e-19 j |
| 10 ev | 1.602180e-18 j |
| 25 ev | 4.005450e-18 j |
| 50 ev | 8.010900e-18 j |
| 100 ev | 1.602180e-17 j |
| 1000 ev | 1.602180e-16 j |
| 10000 ev | 1.602180e-15 j |
| 100000 ev | 1.602180e-14 j |
| 1.000000e+6 ev | 1.602180e-13 j |
| 1.000000e+9 ev | 1.602180e-10 j |
| 1.000000e+12 ev | 1.602180e-7 j |
Joules to Electron Volts Conversion Table
| Joules (j) | Electron Volts (ev) |
|---|---|
| 1.000000e-19 j | 0.6241495962 ev |
| 1.602180e-19 j | 1 ev |
| 1.000000e-18 j | 6.2414959618 ev |
| 1.000000e-17 j | 62.4149596175 ev |
| 1.000000e-15 j | 6241.4959617521 ev |
| 1.000000e-12 j | 6.241496e+6 ev |
| 1.000000e-9 j | 6.241496e+9 ev |
| 1.000000e-6 j | 6.241496e+12 ev |
| 0.001 j | 6.241496e+15 ev |
| 1 j | 6.241496e+18 ev |
Electron Volts to Joules in Everyday Objects
Common real-world examples that make Electron Volts and Joules easy to picture at a glance.
| Electron Volts (ev) | Joules (j) | |
|---|---|---|
| A thermal-energy electron at 70°F room temperature | 0.025 ev | 4.005450e-21 j |
| A red photon (650 nm) | 1.9 ev | 3.044142e-19 j |
| A blue photon (450 nm) | 2.75 ev | 4.405995e-19 j |
| Breaking a molecular bond | 4 ev | 6.408720e-19 j |
| A dental X-ray photon | 60000 ev | 9.613080e-15 j |
| A proton in the LHC | 6.500000e+12 ev | 1.041417e-6 j |
When You Need Electron Volts to Joules Conversions
Semiconductor Band-Gap Calculations
LED and solar-panel datasheets quote band gaps in eV — silicon at 1.12 eV, GaN at 3.4 eV. Converting to 1.79444e-19 J and 5.44741e-19 J lets engineers at US solar and LED companies compute junction power densities in pure SI units.
Photon Energy in Spectroscopy
Spectra are labeled in eV while detector energy budgets are in joules. A 2.33 eV green laser line becomes 3.73e-19 J per photon — multiply by photon flux and optical power falls out in watts.
Radiation and Dosimetry Coursework
Nuclear engineering courses quote gamma energies in MeV, but absorbed-dose formulas need joules per kilogram. A 0.662 MeV cesium-137 photon converts to 1.06064e-13 J before entering dose equations.
Particle Accelerator Problem Sets
Accelerator physics mixes beam energies in TeV with SI kinematics. An LHC proton at 6.5 TeV (6.5e12 eV) carries just 1.04142e-6 J — you'd need on the order of 60 billion of them to heat an 8-oz cup of coffee.
Related Energy Conversions
How to Use
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1
Enter Electron Volts
Type the eV value from your problem set — single-digit eV for photons and chemical bonds, or scientific notation like 6.5e12 eV for particles out of Fermilab or CERN
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2
View Joules
The SI answer appears instantly: a 2 eV visible photon becomes 3.20436e-19 J, ready for any equation that demands SI units
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3
Copy or Swap
Copy the result or hit Swap to convert joules back to electron volts (1 J = 6.2415e18 eV) for a quick reverse check
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Keep the Scale in Mind
One joule equals about 6.2415e18 eV, so everyday energy means astronomically big electron-volt counts — charging your smartphone takes roughly 54,000 J, or about 3.37e23 eV. If your answer isn't vanishingly small, an exponent slipped somewhere
Why Use Be Converter?
Instant Conversion
Get precise eV-to-joule results in real time as you type — built for homework crunches, AP Physics exams, and lab reports
Scientific Notation Handled Cleanly
Type 2.5 eV or 6.5e12 eV and get exact answers using 1 eV = 1.60218e-19 J — no manual exponent math, no calculator fumbling
Conversion Table
Quick reference across physics scales — a 1.9 eV red photon (3.04e-19 J), a 5,000 eV X-ray photon (8.01e-16 J), and a 6.5 TeV LHC proton (1.04e-6 J)
Bidirectional
One click swaps electron volts and joules so you can check both directions of a calculation
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Frequently Asked Questions
How many joules are in 1 electron volt?
How do I convert 10 eV to joules?
How many electron volts are in 1 joule?
Why do physicists use eV instead of joules?
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How many joules is 1 MeV?
Is an electron volt energy or voltage?
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About Electron Volts to Joules Converter
Our free online electron volts to joules calculator delivers instant, accurate energy conversions for physics coursework, chemistry labs, and materials science — whether you're cramming for the AP Physics exam or running calculations at a national lab. The electron volt is the natural energy unit of the microscopic world: photon energies, chemical bond strengths, semiconductor band gaps, X-ray emissions, and particle accelerators like Fermilab and the LHC are all measured in eV or its multiples (keV, MeV, GeV, TeV). The SI joule remains the required unit for formal equations and dimensional analysis. Using the conversion 1 eV = 1.60218e-19 J, this tool bridges the two systems instantly — enter any value in electron volts and get the joule equivalent in clean scientific notation.
Expert Tips for eV to J Conversion
The factor is 1.60218e-19 J per eV. In reverse, 1 J = 6.2415e18 eV. Memorize the exponent pair (-19 / +18) and you can sanity-check any conversion by magnitude alone.
Prefix shortcuts: 1 keV = 1.60218e-16 J, 1 MeV = 1.60218e-13 J, 1 GeV = 1.60218e-10 J, 1 TeV = 1.60218e-7 J. The LHC runs protons at 6.5 TeV (1.04e-6 J each), while Fermilab's Main Injector delivers 120 GeV protons (1.92e-8 J each).
Photon work: E = hc/λ gives energy in eV when λ is in nanometers as 1240/λ. A 620 nm red photon is 2.0 eV; converting to joules (×1.60218e-19) yields 3.2e-19 J.
Semiconductor band gaps: silicon at 1.12 eV is 1.79444e-19 J and GaN at 3.4 eV is 5.44741e-19 J. Converting to joules is required when computing power densities from photon flux — the daily math behind chip fabs in Arizona and Texas.
Chemistry crossover: bond energies often appear in kJ/mol. Since 1 eV per particle equals 96.48 kJ/mol, a 4 eV bond is about 385.9 kJ/mol — convert to joules per particle (6.40872e-19 J) first for consistency.