Chemical Equation Balancer
Any equation, including the redox ones that take a page by hand.
Any equation, including the redox ones that take a page by hand. Handles the awkward cases, not just the tidy ones.
Separate species with + or commas. Case matters: Co is cobalt, CO is carbon monoxide.
Brackets and polyatomic ions work: Ca3(PO4)2.
Balanced equation
2KMnO4 + 16HCl → 2KCl + 2MnCl2 + 8H2O + 5Cl2
Coefficients 2, 16, 2, 2, 8, 5
Balancing is solved here as a system of linear equations rather than by trial and error: one equation per element, one unknown per species, solved with exact fractions so nothing is lost to rounding. That is why it handles the awkward redox equations that take a page by hand. The coefficients returned are the smallest whole numbers that work — any multiple of them balances equally well, which is why 2H₂ + O₂ → 2H₂O is preferred over 4H₂ + 2O₂ → 4H₂O. If an equation refuses to balance, the usual cause is a missing species. Redox reactions in solution almost always need H⁺, OH⁻ or H₂O adding to one side before the atoms and charges can both work out.
How the Chemical Equation Balancer works
Type the reactants and products and this returns the smallest whole-number coefficients that balance them. It solves the equation as a linear system with exact fractions rather than by trial and error, so the awkward redox equations come out as easily as the simple ones.
Also known as: equation balancer · chemical equation solver · how to balance chemical equations · balance redox equations calculator
Frequently asked questions
How do I balance a chemical equation?
Adjust the coefficients until every element has the same number of atoms on both sides. Formally it is a system of linear equations — one per element — and the balanced equation is the smallest whole-number solution.
Why does my equation refuse to balance?
Almost always a missing species. Redox reactions in solution usually need H⁺, OH⁻ or H₂O adding to one side before both the atoms and the charges work out. It can also mean the reaction as written is really two independent reactions.
Can coefficients be fractions?
The mathematics allows it, and half-coefficients are common when writing formation equations. By convention the answer is scaled to the smallest whole numbers, which is why this returns 2H₂ + O₂ → 2H₂O rather than H₂ + ½O₂ → H₂O.
Does capitalisation matter?
Completely. CO is carbon monoxide and Co is cobalt. This rejects an unrecognisable formula rather than guessing, because a silently misread symbol would give a confidently balanced but wrong equation.
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