How many electronvolts are in one watt-hour?

One watt-hour equals 2.2469385×10²² eV. This follows from 1 Wh = 3600 J and 1 J = 6.241509074×10¹⁸ eV (the reciprocal of the elementary charge 1.602176634×10⁻¹⁹ C, exact since the 2019 SI revision).

Why is the eV value so astronomically large for a small number of watt-hours?

The electronvolt is an incredibly tiny unit — 1 eV ≈ 1.6×10⁻¹⁹ J. A single watt-hour equals 3,600 J, so it contains roughly 2.25×10²² eV. Even a milliwatt-hour (0.001 Wh) holds about 2.25×10¹⁹ eV. Scientific notation is the only practical way to express these results.

What is the exact conversion factor between Wh and eV?

1 Wh = 3600 J and 1 eV = 1.602176634×10⁻¹⁹ J (exact). Therefore 1 Wh = 3600 / 1.602176634×10⁻¹⁹ = 2.2469385463×10²² eV. The elementary charge value has been exact since the 2019 SI redefinition.

How do I enter scientific notation in the input field?

Use standard e-notation: for 1.5×10⁻³ type "1.5e-3". For 2×10²² type "2e22". Most browsers and this tool accept that format directly.

Where is eV used versus watt-hours?

Electronvolts are the natural energy unit in atomic, nuclear, and particle physics — electron binding energies (~eV), X-ray photons (~keV), nuclear reactions (~MeV), and accelerator beams (~GeV to TeV). Watt-hours are the practical unit for electrical energy storage and consumption — batteries, chargers, and utility bills.

Watt Hours to Electronvolts Converter

Enter watt-hours to get electronvolts in scientific notation — or enter eV to convert back. 1 Wh = 2.24694 × 10²² eV.

Energy Converter

Energy in Watt-Hours (Wh)

Electronvolts (eV)

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Kiloelectronvolts (keV)

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Megaelectronvolts (MeV)

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Gigaelectronvolts (GeV)

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1 Wh = 2.24694×10²² eV | 1 eV = 4.45049×10^-26 Wh

Wh ↔ eV Reference Table

Common energy values and their watt-hour/electronvolt equivalents

Watt-Hours (Wh)	Electronvolts (eV)	Context

1 Wh = 3600 J; 1 eV = 1.602176634×10^-19 J (exact, 2019 SI). Therefore 1 Wh = 2.2469385×10²² eV.

Summary

This converter transforms watt-hours (Wh) into electronvolts (eV) using the exact SI-defined relationship: 1 eV = 1.602176634×10⁻¹⁹ J (exact) and 1 Wh = 3600 J, giving 1 Wh = 2.2469385×10²² eV. Because the electronvolt is a subatomic unit and the watt-hour is a macroscopic energy unit, conversion results span 22 orders of magnitude — scientific notation is essential. The tool is bidirectional: enter watt-hours to get eV, or enter eV to get watt-hours.

How it works

Select direction: Wh → eV or eV → Wh.
Enter any numeric value — whole numbers, decimals, or scientific notation (e.g. 0.001 or 1e-3).
The result appears instantly in scientific notation.
Click any result field to copy it to the clipboard.
The reference table below shows common Wh↔eV conversions.

Use cases

Translate battery capacity (Wh) into the equivalent number of electronvolts for physics coursework.
Cross-check particle accelerator energy budgets expressed in eV against real-world watt-hour costs.
Convert solar panel output (Wh) to eV for photovoltaic efficiency calculations.
Verify nuclear reaction Q-values in MeV against the watt-hour energy budget of a lab experiment.
Understand scale: how many eV are stored in a smartphone battery or AA cell.

Frequently Asked Questions

Last updated: 2026-06-19 · Reviewed by Nham Vu