Calculator
Use any unit; the tool can auto-match units.
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%
Result
mode: actual—
The tool can convert mg↔g↔kg and mmol↔mol automatically.
Export
Exports include the results table below. PDF fits standard pages.
Quick unit converter
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Example data
| Example | Mode | Theoretical | Percent | Actual | Units | Load |
|---|---|---|---|---|---|---|
| Aspirin synthesis | Actual | 5.00 | 75 | — | g | |
| Ethyl acetate | Percent | 10.00 | — | 8.20 | g | |
| CuSO₄·5H₂O crystals | Theoretical | — | 70 | 14.00 | g |
Click Load to prefill the calculator with an example scenario.
Results table
| # | Timestamp | Mode | Theoretical | Percent | Actual | Units | Rounded |
|---|
Stoichiometry helper (theoretical yield)
Supports up to three reactants with purity and hydration, and up to three products.
Hydration adds n × 18.01528 g/mol to the base molar mass; purity scales usable amount.
Reactant A
Reactant B
You may leave Reactant B empty to assume excess.
Reactant C
You may leave Reactant C empty to assume excess.
Product P1
Product P2
Product P3
Helper results
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| # | Product | Coeff | Moles | Grams | Send |
|---|
Extent is limited by the smallest nᵢ/coeffᵢ across provided reactants.
Formula used
Actual yield A
Given theoretical yield T and percent yield Y%:
A = (Y / 100) × T
Percent yield Y%
Y% = (A / T) × 100
Theoretical yield T
T = A × (100 / Y)
Use consistent units. Purity reduces usable mass; hydration increases formula molar mass.
How to use this calculator
- Choose which variable to calculate: actual, percent, or theoretical.
- Use the Stoichiometry helper to set reactants and products.
- Click Compute theoretical products to get moles and grams.
- Select a product and Send its grams to the main calculator.
- Export your table with the CSV or PDF buttons.
FAQs
Yes. Define up to three product coefficients and molar masses. The tool computes moles and grams for each based on the limiting extent and lets you send any product to the main calculator.
The helper converts each reactant to usable moles (purity and hydration applied), then finds the smallest ratio of moles to coefficient. That ratio sets the reaction extent for all products.
Yes. Recompute if needed, pick the product from the dropdown, and click Send selected grams. You can repeat this to compare multiple scenarios.
Enter its base molar mass and the number of hydration waters if applicable. For gases, you can still compute moles and convert to grams for mass balance checks.
It relies on your balanced coefficients. If the equation is balanced, the computed products will be consistent. We can add a balancer if you’d like.