In our conversations with window and door dealers across Florida, we frequently hear owners make statements like: "We mark up all our manufacturer windows by 40%, so we run at a 40% gross margin."
Whenever we hear that, we know the dealership has a serious cash leak.
Because in accounting arithmetic, a 40% markup is NOT a 40% gross margin. A 40% markup is a 28.6% gross margin.
The Crucial Arithmetic Difference
While the terms are often used interchangeably on the sales floor, their formulas represent completely different financial realities:
Worked example · illustrative numbers, not industry data
| Metric | Formula | Example on 10,000 Factory Cost |
|---|---|---|
| Markup | (Selling Price - Cost) / Cost | 10,000 cost × 1.40 = 14,000 Retail (4,000 profit) |
| Gross Margin | (Selling Price - Cost) / Selling Price | 4,000 profit / 14,000 retail = 28.6% Margin |
Worked example: if your company’s overhead (showroom rent, office staff, sales commissions, vehicle insurance, marketing CAC) requires a 35% gross margin to break even, pricing with a 40% markup means you lose money on every single job you install.
How to Calculate True Target Margin
To achieve a true 40% gross margin, you cannot multiply your cost by 1.40. You must divide your cost by (1 - Margin):
Selling Price = Cost / (1 - 0.40) = Cost / 0.60 = Cost × 1.667
Worked example: on that same 10,000 factory cost, selling at a true 40% gross margin requires a retail price of 16,667—not 14,000. That is a 2,667 discrepancy on a single job.
Why Quote Converter Pro™ Solves This Forever
In Quote Converter Pro™, owners price the way they think about profit, and the margin floors they set hold on every quote.
Conclusion
Markup is what you add to cost; margin is what you keep from revenue. Make sure your quoting software speaks the same language as your profit and loss statement.