Are parentheses supported?

Yes for groups such as Ca(OH)2.

Why did balancing fail?

Usually a typo in a formula, a missing species, or an equation that cannot conserve atoms as written.

Is a balanced equation always a real reaction?

No. Atom balance is necessary, not sufficient, for chemical feasibility or safety.

Chemical Equation Balancer

Find integer coefficients that conserve atoms—without inventing chemistry your equation does not contain.

Atom conservation

Integer coefficients

Common classroom formulas

Parses a chemical equation and finds the smallest positive integer coefficients that conserve each element across reactants and products.

Limitation: Educational stoichiometry only.

Jump to calculator · Sources & review

Unbalanced equationUse + between species and = or → between sides. Example: Fe + O2 = Fe2O3

How to Balance an Equation

Type the unbalanced reaction, then review the coefficient list.

Write reactants and products with correct element symbols.

Fix formulas first

Balancing cannot repair a wrong formula. Fe2O3 and FeO2 are different species and produce different matrices.

What Balancing Means Here

Each element’s atom count on the left must equal the count on the right after coefficients are applied. The worksheet searches for the smallest positive integers that satisfy those equations.

Balancing Examples

Water formation

Equation

equation:H2 + O2 = H2O

Balanced form

2H2 + O2 = 2H2O

Hydrogen and oxygen atoms both conserve with coefficients 2, 1, 2.

Iron oxidation

Equation

equation:Fe + O2 → Fe2O3

Balanced form

4Fe + 3O2 = 2Fe2O3

Four iron atoms and six oxygen atoms appear on each side.

Check one element

After balancing, pick one element and count atoms on both sides by hand.

Frequently Asked Questions

Yes. Both = and → are accepted as the side separator.

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Atom-Conservation Method

Balancing is a linear algebra problem: coefficients must make every element’s net change zero.

Imperial:For imperial units: Σ (coeff × atoms in reactant) = Σ (coeff × atoms in product)

Formula

Σ (coeff × atoms in reactant) = Σ (coeff × atoms in product)

Element conservation

Σ (coeff × atoms in reactant) = Σ (coeff × atoms in product)

Integer solution

smallest positive integers in the null space

Scientific Background

Assumptions: formulas use standard element symbols, optional parentheses, and integer subscripts; the reaction is closed (no missing species). Limitations: redox half-reactions with electrons, ionic charges, and state symbols are ignored; chemically impossible skeletons may still balance mathematically.

Sources & review

Chemical Equation Balancer documents the references behind its formulas and assumptions. Always treat results as educational estimates, not personalized professional advice.

Last reviewed

July 22, 2026

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