electronvolt to joule Converter
Convert eV to J and back with a live reference table.
1 eV = 1.60218e-19 J\n5 eV = 8.01088e-19 J\n10 eV = 1.60218e-18 J\n25 eV = 4.00544e-18 J\n50 eV = 8.01088e-18 J\n100 eV = 1.60218e-17 J
Why this conversion matters
Electronvolts are natural for atomic and particle energies, but joules help connect them to macroscopic energy units. The widget keeps the direction explicit so you can enter either side of the pair without doing the reciprocal by hand. It is built for quick checks where a calculator, specification sheet, recipe, map, or lab note uses the other unit.
For the default example, 1000000000000000000 eV converts to 0.160218 J. Switching the direction shows the inverse relationship, so 0.160218 J converts back to 1000000000000000000 eV with the same factor.
Formula and privacy note
The calculation uses 1 eV = 1.60218e-19 J. Forward conversion multiplies by that factor, and reverse conversion divides by it. Results are rounded to six significant figures for readable estimates, so very small scientific units and large planning units stay scannable. Check the unit labels before copying a result, especially when similar abbreviations appear in the same project. The reference table is generated from the same constant, and everything runs locally in your browser.
Frequently Asked Questions
What factor does this converter use?
It uses the standard factor 1 eV = 1.60218e-19 J, then applies the reciprocal for the reverse direction.
Why are results rounded?
The main result is rounded to six significant figures so very large and very small values stay readable while preserving the useful precision for quick checks.
Can I convert both directions?
Yes. Choose eV to J or J to eV from the direction menu and the output updates immediately.
Is this converter private?
Yes. The conversion runs entirely in your browser, and the value you enter is not uploaded or stored.
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