Atoms to Moles Calculator

Convert atoms (or molecules) to moles using Avogadro's number. Enter the number of atoms to find how many moles you have.

⚛️ NUMBER OF ATOMS (or molecules)

atoms

MOLES

1 mol

AVOGADRO'S #

6.022 × 10²³

FORMULA

n = atoms / NA

💡 How to Convert Atoms to Moles

What Is a Mole?

A mole is the SI unit for measuring the amount of a substance. One mole of any substance contains exactly 6.02214076 × 10²³ particles — this number is called Avogadro's number (Nₐ). The particles can be atoms, molecules, ions, or any other chemical entity.

Avogadro's number connects the atomic world, where individual atoms are far too small to count directly, to the macroscopic world, where we measure substances in grams. Use our mole calculator to convert between grams, atoms, and liters.

How to Convert Atoms to Moles

Atoms to Moles Formula

n = atoms / Nₐ

Where:

n = number of moles
atoms = number of atoms or molecules
Nₐ = Avogadro's number = 6.022 × 10²³ /mol

For example, if you have 3.011 × 10²³ atoms of carbon:

n = 3.011 × 10²³ / 6.022 × 10²³ = 0.5 mol

Moles to Atoms

To convert in the reverse direction (moles to atoms), multiply by Avogadro's number: atoms = n × Nₐ. For instance, 2 moles of iron contains 2 × 6.022 × 10²³ = 1.204 × 10²⁴ atoms. Once you know the number of moles, you can convert to grams using the molar mass.

6.022 × 10²³ atoms = 1 mole. This is true for any element or compound.