Titration Calculator
The unknown concentration of a sample from a titration: titrant molarity and volume at the equivalence point, the mole ratio from a balanced equation, and the sample volume, with the moles and mass of analyte.
Result…
How it's calculated
Moles of titrant = molarity × volume Moles of analyte = moles of titrant × (analyte coefficient ÷ titrant coefficient) Analyte concentration = moles of analyte ÷ sample volume Mass = moles × molar mass
At the equivalence point the titrant added has reacted exactly with the analyte in the ratio given by the balanced equation. Multiplying the titrant’s molarity by the volume delivered (in litres) gives its moles; the coefficients turn that into moles of analyte, and dividing by the sample volume gives the unknown concentration. The calculator can read the ratio from an equation, balancing it if needed and taking the analyte’s molar mass from the CIAAW 2024 abridged atomic weights, or you can enter the coefficients. It covers acid–base, redox and precipitation titrations alike, as long as the equation is right.
Your numbers, step by step
About the Titration calculator
This titration calculator works out the unknown concentration of a sample from your burette results. Enter the molarity of the titrant, the volume used to reach the equivalence point and the volume of the sample in the flask, and give the mole ratio either as a chemical equation or as two coefficients. With an equation it checks the balance, balances it for you if needed, and reads the analyte’s molar mass from its formula, so you also get the moles and grams of analyte in the sample and the concentration in g/L. It suits acid–base, redox and precipitation titrations in school, college and quality-control labs. The steps go from moles of titrant, through the mole ratio, to the concentration, using your own numbers at each stage.
How to use it
- Under “Mole ratio from”, choose “A chemical equation” and type it in “Balanced equation”, or choose “Coefficients I enter”.
- With an equation, set “The titrant is the” to the reactant in the burette; the other of the first two reactants is the analyte.
- Enter the “Molarity of the titrant” and the “Titrant volume at the equivalence point”, which is the final burette reading minus the initial one.
- Enter the “Volume of the sample (analyte)” and choose the units.
- Read the analyte concentration, the moles of each species and, with an equation or a molar mass, the mass of analyte.
Worked example
20.0 mL of hydrochloric acid needs 22.4 mL of 0.100 mol/L sodium hydroxide: HCl + NaOH → NaCl + H2O, a 1 : 1 ratio. Moles of NaOH = 0.100 × 0.0224 L = 0.00224 mol, so moles of HCl = 0.00224 mol. The concentration is 0.00224 ÷ 0.0200 L = 0.112 mol/L. The sample held 0.00224 × 36.458 g/mol = 0.0817 g of HCl, or 4.08 g/L.
Updated
Questions people ask
How do I calculate concentration from a titration?
Multiply the titrant’s molarity by its volume in litres to get moles, convert to moles of analyte with the mole ratio from the balanced equation, then divide by the sample volume in litres.
What is the titration formula with a mole ratio?
C(analyte) = C(titrant) × V(titrant) × (analyte coefficient ÷ titrant coefficient) ÷ V(sample). For sulfuric acid with sodium hydroxide the ratio is 1 : 2, so the acid’s moles are half the base’s.
Why can’t I just use M1V1 = M2V2?
That shortcut only works when the ratio is 1 : 1. For H2SO4 or H3PO4 against NaOH it gives the wrong answer unless you include the coefficients, which this calculator does.
Is the end point the same as the equivalence point?
Not quite. The end point is where the indicator changes colour; a well-chosen indicator changes very close to the equivalence point, but the small difference is a source of error. Repeat runs and average the concordant ones.
Where do the molar masses come from?
From the formula in your equation, using the CIAAW 2024 abridged atomic weights, the same ones the molar mass calculator uses. The stoichiometry calculator handles other reaction amounts and limiting reagents.