Business & Economics 5 min read · Published August 24, 2026

Author: Marcus Chen (Business Modeling Contributor)

Why a 40% markup only yields a 28.5% profit margin, and how miscalculations can destroy your unit economics.

### The Classic Pricing Trap Many founders make the costly mistake of assuming that adding a 30% markup onto their unit production costs will guarantee a 30% gross profit margin. Here is the exact mathematical reality: * **Cost:** $100 * **30% Markup Price:** $130 * **Gross Profit:** $30 * **Actual Margin:** $30 / $130 = **23.07%** To achieve a true 30% gross profit margin, you must divide your cost by (1 - Margin), which requires pricing the item at **$142.86**.