# Mole Calculator

Free mole calculator. Convert between moles, grams, and number of particles. Uses Avogadro's number and molar mass for accurate conversions.

## What this calculates

Convert between moles, grams, and particles. Enter the molar mass and any one known value to calculate the others. Uses Avogadro's number (6.022 × 10²³) for particle conversions.

## Inputs

- **Solve For** — options: Moles (from grams), Grams (from moles), Particles (from moles), Moles (from particles) — Select what you want to calculate.
- **Mass** (g) — min 0 — Mass of the substance in grams.
- **Molar Mass** (g/mol) — min 0.001 — Molar mass (molecular weight) of the substance.
- **Moles** (mol) — min 0 — Amount of substance in moles.
- **Number of Particles** — min 0 — Number of atoms, molecules, or formula units.

## Outputs

- **Result** — formatted as text — The calculated value.
- **Moles** (mol) — Amount in moles.
- **Grams** (g) — Mass in grams.
- **Formula** — formatted as text — Calculation explanation.

## Frequently Asked Questions

**Q: How do I convert grams to moles?**

A: Divide the mass in grams by the molar mass of the substance. moles = grams / molar mass. For example, 36 g of water (molar mass 18.015 g/mol) = 36 / 18.015 = 2.0 moles.

**Q: How do I convert moles to grams?**

A: Multiply the number of moles by the molar mass. grams = moles × molar mass. For example, 3 moles of NaCl (molar mass 58.44 g/mol) = 3 × 58.44 = 175.32 grams.

**Q: What is the difference between a mole and a molecule?**

A: A molecule is a single particle made of bonded atoms (like one water molecule H₂O). A mole is a counting unit equal to 6.022 × 10²³ particles. One mole of water contains 6.022 × 10²³ water molecules.

**Q: Where do I find the molar mass?**

A: Look up atomic masses on the periodic table and add them for each atom in the formula. For H₂O: 2(1.008) + 15.999 = 18.015 g/mol. Many references and our molecular weight calculator can do this for you.

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Source: https://vastcalc.com/calculators/chemistry/mole
Category: Chemistry
Last updated: 2026-04-21