BYTETOOLS

Chemical Equation Balancer

Balance any chemical equation automatically. Enter reactants and products and get the smallest whole-number coefficients plus an atom-by-atom check.

Balanced equation

C3H8 + 5O2 → 3CO2 + 4H2O

Coefficients: 1 : 5 : 3 : 4 — the smallest whole numbers that satisfy conservation of mass.

Atom check

ElementAtoms on the leftAtoms on the rightBalanced?
C33Yes
H88Yes
O1010Yes

The balancer solves the element × species matrix exactly with integer fractions, so the coefficients are never rounded. Ionic charges are not modelled, so half-equations such as MnO4⁻ + 5e⁻ are outside its scope.

What is the Chemical Equation Balancer?

Balancing an equation means finding the smallest whole-number coefficients that give the same number of atoms of each element on both sides. For propane combustion the answer is C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O.

  • Exact fraction arithmetic — no floating-point rounding
  • Smallest positive whole-number coefficients, reduced by GCD
  • Atom-by-atom verification table
  • Handles nested brackets and multi-letter element symbols
  • Clear messages for unbalanceable or ambiguous equations
  • Runs entirely in your browser — nothing is uploaded

How to use the Chemical Equation Balancer

  1. 1

    Type the unbalanced equation, e.g. C3H8 + O2 -> CO2 + H2O.

  2. 2

    Separate species with + and the two sides with -> or =.

  3. 3

    Read the balanced equation with its coefficients.

  4. 4

    Check the atom table to confirm both sides match.

  5. 5

    Copy the balanced equation into your work.

About the Chemical Equation Balancer

The ByteTools Chemical Equation Balancer takes an unbalanced equation and returns the coefficients that satisfy conservation of mass. Write the reactants and products separated by an arrow, and the tool parses every formula, builds an element-by-species matrix and solves it for the smallest set of positive whole numbers.

The solve uses exact integer fractions rather than floating-point arithmetic, so coefficients are never rounded or approximated — a balanced equation is genuinely balanced. An atom-check table underneath lists every element with its total on each side so you can verify the answer yourself, which is exactly what an exam question expects you to show.

The parser handles nested brackets like Al2(SO4)3, and the whole thing runs inside your browser in JavaScript. No equation is sent to a server, so it is fast, private and available offline.

Frequently asked questions

How do you balance a chemical equation?

Adjust the coefficients in front of each formula until every element has the same atom count on both sides, never changing subscripts. This tool does it algebraically by solving the element-by-species matrix, which always finds the answer without trial and error.

What is the balanced equation for the combustion of propane?

C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O. The three carbons give three CO₂, the eight hydrogens give four H₂O, and those together need ten oxygen atoms, which is five O₂ molecules.

Why does it say my equation cannot be balanced?

Usually an element appears on only one side, or a formula was mistyped so the atom counts can never match. Check the symbols and subscripts, and make sure every product really is formed from the reactants you listed.

What does more than one independent balance mean?

It means the system has several solutions, which normally happens when a species appears unchanged on both sides or when two separate reactions have been written as one. Split the equation into single reactions and balance each of them.

Can it balance ionic half-equations with charges?

No. The balancer works on atoms only and does not model electric charge, so half-equations containing electrons or ionic charges are outside its scope. Write the full molecular equation instead.

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