Chemistry
Avogadro's Number Calculator
Convert between an amount of substance in moles and the number of particles it contains, using Avogadro's constant.
Your inputs
Change any value to update the result instantly.
Particles in this amount (N)
6.0221 × 10²³ particles
Moles from the particle count you entered
1 mol
Avogadro's constant (N_A)
6.02214076 × 10²³ mol⁻¹ (exact)
Particles per millimole
6.0221 × 10²⁰
Avogadro's constant has been an exact defined value since the 2019 revision of the SI.
What this calculator does
Converts between an amount of substance in moles and the number of particles, using the defined value of the Avogadro constant.
What your result means
The headline is how many particles (atoms, molecules, ions or formula units) the entered amount contains.
Formula and working
N = n × N_A and n = N ÷ N_A
- 1
Collect the inputs
Amount of substance (n) = 1 mol; Particle count to convert back (N) = 6.0221 × 10²³ particles
- 2
Apply the formula
N = n × N_A and n = N ÷ N_A
- 3
Result
Particles in this amount (N) = 6.0221 × 10²³ particles
Frequently asked questions
Symbols and assumptions
- n
- Amount of substance in moles
- N
- Number of particles
- N_A
- Avogadro constant, 6.02214076 x 10^23 mol^-1 (exact)
- • The substance is a pure chemical species so that one mole always contains N_A entities.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • It counts entities only; it says nothing about mass unless you also know the molar mass.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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