Use this chemistry calculator to reproduce a named relationship with explicit quantities and units for study, laboratory planning, or an independent numerical check.

Valence electrons

Valence electrons of the free neutral atom.

Nonbonding electrons

Lone-pair (nonbonding) electrons on the atom.

Bonding electrons

Total electrons in bonds shared by the atom.

Compute the formal charge as valence electrons minus nonbonding electrons minus half of the bonding electrons. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Formal charge

The resulting formal charge returned as an integer.

• Bond, orbital, and structure rules are simplified representations. Resonance, relativistic effects, electron correlation, molecular geometry, oxidation state, and the measurement or computational method affect tabulated and predicted values.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check units and significant figures, compare the result with limiting cases, and use measured or source-specific constants where available. Laboratory, safety, and regulatory decisions require validated methods and appropriate uncertainty analysis.

• Bond Order Calculator

  Compute molecular orbital bond order as (bonding electrons − antibonding electrons) / 2.

• Equivalent Moles Calculator

  Compute equivalents of a substance as moles times its valence (protons, hydroxides, or electrons transferred).

• Charge From Moles Electrons

  Compute the total charge as moles of electrons times the Faraday constant.