Calculate the atomic mass of a chemical element, expressed in daltons (Da).

All 120 elements from the current periodic table are available from the dropdown menu, but you're also free to input your own values to be calculated.

Tips for This Calculator

  • Elements are filtered as you type by their name and symbol.
  • Certain elements have alternative names or spellings and for these specific elements, any alternatives are also provided.
  • Simplifying the calculation will set the masses of protons and neutrons to 1 dalton, while completing ignoring electrons.

Subatomic Particle Masses

Proton 1.007276466879 daltons
Neutron 1.00866491588 daltons
Electron 0.00054857990907 daltons
Simplify the calculation

Tool History

Revisions made to this tool will be documented below, organized by date in descending order.

Thursday, February 2, 2023

  • The proton and neutron counts for ununennium and unbinilium have been corrected.

Sunday, September 11, 2022

  • Initial release.

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