Free Chemistry Calculator

Theoretical Yield Calculator

Compare two or more reactants to identify the limiting reagent and calculate ideal product yield. Enter each reactant formula, balanced coefficient, amount, and unit, plus the target product formula and coefficient.

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Calculate limiting reagent and theoretical yield

Enter one reactant per line as formula, coefficient, amount, unit. Coefficients must come from a balanced equation.

Supported amount units: g, mg, mol, mmol.
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What is a theoretical yield calculator?

A theoretical yield calculator compares available reactant amounts against balanced coefficients. The smallest available moles-per-coefficient value identifies the limiting reagent. Balance the equation first with the Chemical Equation Balancer.

How does the limiting reagent calculation work?

Each reactant amount is converted to moles and divided by its coefficient. The minimum ratio defines the reaction extent, which is multiplied by the product coefficient and product molar mass.

What formulas calculate theoretical yield?

Reaction extent ξ = min(nᵢ ÷ νᵢ). Product moles = ξ × νproduct. Theoretical product mass = product moles × product molar mass. Percent yield = actual mass ÷ theoretical mass × 100.

How do you enter reactants for theoretical yield?

Enter one reactant per line as formula, coefficient, amount, and unit. Use the Grams to Moles Calculator to check any mass conversion and the Stoichiometry Calculator for a one-known-to-one-target conversion.

What do theoretical yield results mean?

The main result is the maximum modeled product mass if the limiting reagent reacts completely according to the entered equation. The table shows each reactant’s available moles and excess remaining after the ideal extent.

Why is actual yield usually lower than theoretical yield?

Incomplete conversion, equilibrium, competing reactions, impure reagents, transfer loss, isolation loss, measurement uncertainty, and product moisture can change actual yield. A result above 100% often indicates impurities, retained solvent, or input error; check it with the Percentage Calculator.

Who should use this limiting-reagent calculator?

It is useful for general chemistry and preliminary reaction planning with known balanced stoichiometry. Confirm formula masses with the Molar Mass Calculator and follow approved safety and process procedures for laboratory or production work.

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Frequently asked questions about Theoretical Yield

It is the maximum amount of specified product predicted from the limiting reagent under the entered stoichiometry.
It is the reactant with the smallest available moles divided by its balanced coefficient.
Use formula, coefficient, amount, unit, such as H2, 2, 4.00, g.
Yes. Each line may use g, mg, mol, or mmol.
Yes. Incorrect coefficients produce an incorrect limiting reagent and yield.
Divide actual product mass by theoretical product mass and multiply by 100.
A reported value can exceed 100%, but it usually signals retained solvent, impurities, measurement problems, or incorrect inputs.
No. It is a stoichiometric maximum and does not model kinetics or equilibrium time.

Sources and methodology

The calculation method and explanatory context can be checked against these authoritative primary references.

Scope: This free tool supports learning and planning. Confirm important laboratory, academic, medical, environmental, or industrial work with current protocols and qualified review.
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