Percent Yield Calculator

Calculate percent yield from actual and theoretical yield. A key metric for evaluating reaction efficiency.

🧪 ACTUAL YIELD

📐 THEORETICAL YIELD

PERCENT YIELD

85 %

LOST / WASTED

15 g

FORMULA

% = (actual / theoretical) × 100

💡 How to Calculate Percent Yield

What Is Percent Yield?

Percent yield measures how efficient a chemical reaction is by comparing the amount of product actually obtained (actual yield) to the maximum amount that could theoretically be produced (theoretical yield). A yield of 100% would mean every atom of reactant was converted to product with no losses.

How to Calculate Percent Yield

Percent Yield Formula

% Yield = (Actual Yield / Theoretical Yield) × 100

In practice, percent yields are always less than 100% due to:

Incomplete reactions (equilibrium)
Side reactions producing unwanted products
Loss during transfer, filtration, or purification
Impure reactants

Typical Yields by Reaction Type

Simple precipitation reactions typically achieve 90–99% yield. Organic synthesis reactions vary widely from 60–90%. Pharmaceutical manufacturing usually targets 80–95%. Multi-step synthesis yields are multiplicative — if each of 5 steps has 90% yield, the overall yield is 0.9⁵ = 59%.

Typical lab yields: organic synthesis 60-90%, pharmaceutical manufacturing 80-95%, simple precipitation reactions 90-99%.