chemistry

Molar Mass and Formula Calculator

Parse chemical formulas, hydrates and parentheses; show element contributions and convert between mass and moles.

Calculator

Formula

M = Σ(nᵢAᵢ)

Assumptions and limits

Atomic weights are representative IUPAC values; isotopically enriched samples need isotope-specific masses.

Example

Editable worked example

The calculator starts with an editable example.

Sources

Chemistry 2e — OpenStax

Frequently asked questions

Are my inputs uploaded?

No. This calculator runs locally in your browser. Inputs are placed in a URL only when you explicitly copy a share link.

Why are units converted first?

Canonical units prevent scale errors when inputs use mixed units. The result is converted back to your selected output unit afterward.

Does the result replace professional judgment?

No. The result applies only to the stated model and assumptions. Qualified people should review high-risk engineering, medical, or laboratory decisions.