Calculating your moles is straightforward once you know the Grams to Moles formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Grams to Moles Calculator.
What is Grams to Moles?
The Grams to Moles calculation tells you your moles from a few simple inputs. The figure you are solving for here is the moles.
The Grams to Moles formula
The core formula is:
Moles = Mass of substance ÷ Molar Mass of substanceHere is what each input means:
- Mass of substance — a value measured in g. Example: 18 g.
- Molar mass — a value measured in g/mol. Example: 18 g/mol.
How to calculate it step by step
- Write down the mass of substance (for example, 18 g).
- Write down the molar mass (for example, 18 g/mol).
- Apply the formula above to get your moles.
- Double-check the result with the Grams to Moles Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Mass of substance | 18 g |
| Molar mass | 18 g/mol |
| Moles | 1.0000 |
With mass of substance of 18 g and molar mass of 18 g/mol, the moles works out to 1.0000.
Example 2
With mass of substance of 36 g and molar mass of 18 g/mol, the moles works out to 2.0000.
| Result | Value |
|---|---|
| Moles | 2.0000 |
Example 3
With mass of substance of 9 g and molar mass of 18 g/mol, the moles works out to 0.5000.
| Result | Value |
|---|---|
| Moles | 0.5000 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
Prefer not to do the maths by hand? — the Grams to Moles Calculator does it instantly, for free, with the formula and a worked example built in.
Related calculators
Continue exploring science calculators with these tools: Impulse Calculator, Elastic Potential Energy Calculator, Thermal Expansion Calculator, Buoyancy Force Calculator, RPM to Linear Speed Calculator.