Chemical Equation Balancer
Balance a neutral chemical equation using exact element conservation. Return the smallest positive integer coefficients and an atom-count check for every element.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Count atoms of each element in every formula. Set reactant counts equal to product counts and solve the resulting homogeneous linear system with exact fractions. Scale the unique positive ratio to the smallest whole-number coefficients.
For each element: Σreactant(coefficient×atom count)=Σproduct(coefficient×atom count)
Worked example
H2+O2→H2O balances as2H2+O2→2H2O. Both sides then contain4 hydrogen atoms and2 oxygen atoms.
Assumptions and input details
Use1–4 formulas on each side, up to8 species and12 elements. Enter one ->, → or =, and separate species with+. Formulas support parentheses and hydrates; charges, isotopes, phase labels and pre-entered reaction coefficients are unsupported. The shared atomic table supports84 elements. Only equations with a unique coefficient ratio and positive coefficients for every listed species are accepted; coefficients are capped at1e6. Atom balance alone does not establish that a reaction occurs or specify reaction conditions.
References: OpenStax balancing equations
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Atom counts, matrix elimination and the final reduced integer coefficients use exact arithmetic.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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