About the Molecular Weight Calculator

The Molecular Weight Calculator parses any valid chemical formula — including nested parentheses like Ca₃(PO₄)₂ — and returns the molecular weight, elemental composition by mass percentage, and optionally the number of moles for a given mass.

How to use the Molecular Weight Calculator

  1. Type the chemical formula (e.g. H2SO4 or Ca3(PO4)2).
  2. Optionally enter a mass in grams for mole calculation.
  3. Click Calculate.

Frequently asked questions

Is this tool free to use?

Yes. The Molecular Weight Calculator is completely free with no sign-up and no limits.

Is my data uploaded to a server?

No. All calculations run in your browser using JavaScript. Nothing is sent to any server.

Does it work offline?

Yes. Once the page is loaded, all computations work without an internet connection.

Does it work on mobile?

Yes, it works in any modern browser on desktop, tablet and mobile.

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Related keywords

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