# Molar Mass C12 Constant

Use Molar Mass C12 in Calcul.io. See what this built-in constant represents, enter it in an editable calculation, and review related values and units.

## molarMassC12

Molar mass constant of carbon-12

Try it yourself:

```calculio
molarMassC12
```

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## Molar mass of carbon-12

**molarMassC12** gives the molar mass associated with carbon-12, a key reference in atomic-mass conventions.

## Use

Compare it with the [molar mass constant](https://calcul.io/constants/molarMass/index.md) and [atomic mass constant](https://calcul.io/constants/atomicMass/index.md). Use [to()](https://calcul.io/function/to/index.md) for grams per mole and [division](https://calcul.io/function/divide/index.md) for amount calculations.

## Caveat

Natural carbon samples have isotopic variation, so their average molar mass need not equal a pure isotope reference.

[All constants](https://calcul.io/constants/index.md)