How to use the formal charge calculator
Find the formal charge on an atom in a Lewis structure from its valence electrons, lone pair electrons and bonds. Enter valence electrons of atom, non-bonding electrons, bonds to atom in the fields above; the formal charge, electrons owned by atom are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “formal charge”, “Lewis structure charge”, “how to calculate formal charge”, “calculate formal charge”, “find formal charge”.
Formula
Variables
- V — Valence electrons of atom (electrons)
- N — Non-bonding electrons (electrons)
- B — Bonds to atom (bonds)
Worked example
With valence electrons of atom = 5 electrons, non-bonding electrons = 2 electrons, bonds to atom = 3 bonds, the calculator gives formal charge ≈ 0; electrons owned by atom ≈ 5 electrons.
Frequently asked questions
What is the formal charge calculator used for?
Find the formal charge on an atom in a Lewis structure from its valence electrons, lone pair electrons and bonds. It helps with questions such as “formal charge”, “Lewis structure charge”, “how to calculate formal charge”.
What is the formula for the formal charge calculation?
Formal charge = V-N-B. Electrons owned by atom (electrons) = N+B. Here V is valence electrons of atom (electrons), N is non-bonding electrons (electrons), B is bonds to atom (bonds).
What inputs do I need for the formal charge calculator?
You need valence electrons of atom in electrons, non-bonding electrons in electrons, bonds to atom in bonds. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the formal charge calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the formal charge result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.