Molar Mass Calculator
Convert moles to grams and grams to moles straight from a chemical formula. The molar mass is computed for you from sourced NIST/CIAAW atomic weights, with the particle count.
Molar mass
Enter a formula
Atomic masses are source-stamped.
NIST Atomic Weights and Isotopic Compositions
| Element | Atoms | Atomic mass | Contribution | Mass percent |
|---|
Moles to Grams and Grams to Moles
Result
Enter a formula and amount
Molar mass is derived from the formula, so you never look one up.
NIST Atomic Weights and Isotopic Compositions
| Quantity | Value |
|---|
grams = moles * molar mass; moles = grams / molar mass; particles = moles * 6.02214076e23
How?
How this is calculated
The parser expands the formula into element counts and multiplies each count by its bundled standard atomic weight to get the molar mass M. Conversions apply n = m / M and its inverse, and the particle count uses the exact SI Avogadro constant 6.02214076e23 per mole (2019 redefinition). Because M is greater than zero for any parseable formula, grams to moles can never divide by zero. For ionic compounds the gram-per-mole value is a formula mass; the tool does not call a unit such as NaCl a molecule.
Formula: grams = moles * molar mass; moles = grams / molar mass; particles = moles * 6.02214076e23
Sources
- NIST Atomic Weights and Isotopic Compositions. NIST. Retrieved .
- OpenStax Chemistry 2e, Formula Mass and the Mole Concept. OpenStax. Retrieved .
- NIST/CODATA Avogadro constant. NIST. Retrieved .
Method last reviewed