Atomic mass unit conversions
The atomic mass unit conversion selector on this page selects the mass/weight measurement unit to convert to starting from atomic mass units (amu). To make a conversion starting from a unit of mass other than atomic mass unit, simply click on the "Reset" button.
About atomic mass unit
The unified atomic mass unit (or dalton) is a unit of mass defined as 1/12 weight of carbon-12 in its nuclear and electronic ground state.
1 u = 1/12 m(12C)
The atomic mass unit (u) is equal to 1.660538921(73) × 10-27 kilograms (1 u = 1.660538921(73) × 10-27 kg), the base unit of mass in the International System of Units (SI). It is also equal to 1,822.88839 electron rest mass (me).
The energy equivalent of 1 amu:
1 amu = 931.494061(21) × 106 eV/c2 = 931.494061(21) MeV/c2 = 0.931494061(21) GeV/c2
The atomic mass unit is used to indicate the mass on an atomic or molecular scale.
Symbol: u or amu (old abbreviation)
Plural: atomic mass units
Also known as: dalton (plural: daltons, symbol: Da)