Chemical Equation Balancer
Type an unbalanced chemical equation to get the balanced one.
| Element | Reactants | Products |
|---|
What this tool does
Balancing an equation means choosing whole-number coefficients so each element has the same number of atoms on both sides. C3H8 + O2 → CO2 + H2O balances as C3H8 + 5 O2 → 3 CO2 + 4 H2O. Type your own equation above, using -> or = between the sides.
Reads each formula, counts its atoms and solves for the smallest whole-number coefficients.
Verifies the result by counting every element on both sides.
How to use it
- Type the equation with reactants on the left and products on the right, using -> or =.
- Use capital letters correctly and brackets for groups, such as Ca(OH)2.
- Read the balanced equation and the atom counts.
- Copy or download the result.
Why use this tool
Finds the smallest whole-number coefficients with exact fraction arithmetic rather than trial and error, and shows an atom count for each element on both sides as proof. Balancing by trial and error is slow for equations with many substances, and a wrong coefficient breaks every stoichiometry calculation that follows. A solver that proves the balance helps students and teachers check their work.
Why we built it
We built the chemical equation balancer to solve with exact fractions and prove the answer with an atom count. Find masses with the molar mass calculator and make solutions with the molarity calculator.
Who this tool is for
- Chemistry students and teachers
- Anyone checking a balanced equation
- Tutors preparing worksheets and answer keys
When to use it
- Chemistry homework and revision.
- Checking a balanced equation from a textbook.
- Preparing worksheets and answer keys.
- Starting a stoichiometry calculation.
How it works
Each substance becomes a column of atom counts, and each element a row. The coefficients must satisfy "atoms on the left minus atoms on the right equals zero" for every element, so they are a solution of a linear system. The tool solves it exactly with fractions, scales the solution to the smallest whole numbers and checks that all coefficients are positive.
Example: Al + Fe2O3 → Al2O3 + Fe. The result is 2 Al + Fe2O3 → Al2O3 + 2 Fe, with 2 Al, 2 Fe and 3 O on each side. For Ca(OH)2 + H3PO4 → Ca3(PO4)2 + H2O it gives 3, 2, 1 and 6.
Charges and states of matter are not used. Equations that mix several separate reactions have more than one valid balancing, and the tool will ask you to split them.
What you give it, and what you get back
| Item | Details |
|---|---|
| Equation | Substances separated by +, with -> or = between the sides. Brackets and hydrates such as CuSO4·5H2O are allowed. |
| Output | The balanced equation with coefficients, and a table of the atoms of each element on each side. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| "Not an element symbol" | A capital or lower-case letter is wrong, such as CO written as Co. | Check capitals: CO is carbon monoxide, Co is cobalt. |
| "Cannot be balanced" | An element appears on only one side, or the formulas are incorrect. | Check every element appears on both sides. |
| "More than one independent way" | The equation combines separate reactions. | Split it into single reactions. |
| Ions and charges | Charges are not read. | Write the neutral compounds instead. |
Assumptions and limitations
- No charges, electrons or states of matter.
- One balancing per equation.
Frequently asked questions
How do I balance a chemical equation?
Choose coefficients so every element has the same number of atoms on both sides. This tool solves it automatically.
Why must equations be balanced?
Because matter is conserved: atoms are rearranged in a reaction but not created or destroyed.
Can it balance equations with brackets?
Yes. Groups like Ca(OH)2 and Fe2(SO4)3 are counted correctly.
What about hydrates?
Write them with a dot, such as CuSO4·5H2O, or with * or a full stop between the parts.
What if the equation cannot be balanced?
The tool says so. Check that the formulas are right and every element appears on both sides.
Is anything sent to a server?
No. Everything runs in your browser and nothing leaves the page.