Frequently Asked Questions
Everything you need to know about the Redox Equation Balancer.
What makes redox equations harder to balance than regular equations?
Redox equations must balance both the atoms of every element and the net ionic charge on each side, since electrons transferred between species must be conserved.
How do I write ionic charge?
Append a caret and the charge to the formula, like Fe^2+ for iron(II), MnO4^- for permanganate, or Cr2O7^2- for dichromate. A bare + or - means a charge of 1.
How do I balance a reaction in acidic solution?
Include H^+ and H2O as explicit species in your equation on the appropriate sides — the calculator will find the coefficients that balance both H and O along with charge.
How do I balance a reaction in basic solution?
Include OH^- and H2O as explicit species instead of H^+ — write out the equation with these species present and let the balancer solve for the coefficients.
What does the 'Charge' row in the verification table mean?
It's the net ionic charge on each side of the equation — for a correctly balanced redox reaction, total charge on the reactant side must equal total charge on the product side.
Can I include electrons (e-) explicitly?
Yes — write 'e' followed by a charge marker like e^- to represent a free electron with charge −1, useful for balancing individual half-reactions.
Why might the balancer say it cannot balance the equation?
This happens if the species you entered can't form a chemically consistent equation — for example, missing species needed to balance oxygen or hydrogen, or a typo in a formula or charge.
How does this differ from the classic half-reaction method?
The half-reaction method balances oxidation and reduction separately by hand, tracking electrons explicitly. This calculator instead solves for atoms and charge simultaneously using linear algebra, arriving at the same balanced result.
Does this work for non-redox equations too?
Yes — if every species has zero charge, the charge constraint is automatically satisfied and the tool behaves like a standard atom-only equation balancer.
Is this calculator free to use?
Yes, completely free with no sign-up, and it runs entirely in your browser.