Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Activities must be dimensionless and measured at equilibrium. Pure solids and liquids have unit activity; this does not balance reactions.
Example Calculation
- Product activities: 2,3
- Product coefficients: 1,1
- Reactant activities: 4
- Reactant coefficients: 1
For A ⇌ B+C with equilibrium activities 4, 2 and 3, K=2×3/4=1.5.
Frequently asked questions
How do I use this calculator?
Enter product activities, product coefficients, reactant activities, reactant coefficients. The result updates automatically. Use Reset to restore the example values.
What method does it use?
ln K=Σν ln(a_products)−Σν ln(a_reactants).. Activities must be dimensionless and measured at equilibrium. Pure solids and liquids have unit activity; this does not balance reactions.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.