Molar mass calculator

Get the molar mass and element breakdown of any chemical formula — parentheses and hydrates supported.

Standard IUPAC atomic weights. Parentheses and square brackets nest, dots separate hydrate parts (CuSO4·5H2O), and a trailing charge (2+, −) is ignored. Isotope notation like C-14 or [13C] is not supported.

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How to use

  1. Enter a formula like H2SO4 or CuSO4·5H2O.
  2. Read the molar mass.
  3. Check the per-element breakdown.

What it supports

IUPAC standard atomic weights. Parentheses, nested groups, hydrates (·H2O), and trailing charge suffixes (2+) are supported; isotope notation like [13C] or C-14 is not.

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