Moles to grams calculator
Enter the formula and the number of moles to see how many grams to weigh. The molar mass comes from the formula automatically.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter chemical formula and amount.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Mass m (g) = moles n × molar mass M (g/mol).
Example
Inputs: Chemical formula = NaOH, Amount = 0.5 mol. Result: Mass: 19.9984 g; Molar mass: 39.9968 g/mol.
Limits and caveats
- The result is for the pure substance; for a 98% pure reagent, divide the mass by 0.98.
Questions about this tool
How many grams are in 0.5 mol of NaOH?
Sodium hydroxide is 39.997 g/mol, so 0.5 mol weighs about 19.998 g.
Do I need to know the molar mass first?
No. Type the correct formula and the tool computes the molar mass.
What about hydrated salts?
Include the water, for example CuSO4·5H2O, because it is part of what you weigh.