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Electron mass
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<table><tbody><tr><th scope="col">Constant</th><th scope="col">Value</th></tr><tr><th scope="row" rowspan="3"><i>m</i>e</th><td>9.1093837139(28)×10−31 <a href="/facts/Kilogram/lU2zbPk8">kg</a></td></tr><tr><td>5.485799090441(97)×10−4 <a href="/facts/Dalton_(unit)/IMATU3vf">Da</a></td></tr><tr><td>0.51099895069(16) <a href="/facts/Electronvolt/YMT1fqX9">MeV/<i>c</i>2</a></td></tr><tr><th scope="row" rowspan="2"><i>m</i>e<i>c</i>2</th><td>8.1871057880(26)×10−14 <a href="/facts/Joule/9ndq9jD2">J</a></td></tr><tr><td>0.51099895069(16) <a href="/facts/Electronvolt/YMT1fqX9">MeV</a></td></tr></tbody></table> <p>In <a href="/facts/Particle_physics/YgIuyj2t">particle physics</a>, the electron mass (symbol: <i>m</i>e) is the <a href="/facts/Mass_in_special_relativity/aRloR0nW">mass</a> of a stationary <a href="/facts/Electron/L0KBo5cW">electron</a>, also known as the <a href="/facts/Invariant_mass/wNGXNBW6">invariant mass</a> of the electron. It is one of the fundamental <a href="/facts/Physical_constant/uI2QvAHw">constants</a> of <a href="/facts/Physics/a7aH2y08">physics</a>. It has a value of about 9.109×10−31 <a href="/facts/Kilogram/lU2zbPk8">kilograms</a> or about 5.486×10−4 <a href="/facts/Dalton_(unit)/IMATU3vf">daltons</a>, which has an <a href="/facts/Mass%25E2%2580%2593energy_equivalence/ExXawGcc">energy-equivalent</a> of about 8.187×10−14 <a href="/facts/Joule/9ndq9jD2">joules</a> or about 0.5110 MeV. </p>