Two percentages, two different prices
Margin measures profit as a share of selling price. Markup measures the amount added as a share of cost. The same percentage produces a different selling price.
- Modeled profit = price − entered costs
- Margin = modeled profit ÷ price
- Markup = modeled profit ÷ entered costs
Compare them with the same $150 cost
Invented example — not a market rate.
25% markup: $150 × 1.25 = $187.50. Profit is $37.50. $37.50 ÷ $187.50 = a 20% margin.
25% margin: $150 ÷ (1 − 0.25) = $200. Profit is $50. $50 ÷ $200 = a 25% margin.
The $50 profit in the second calculation is also a 33.33% markup on $150. JanitorMath uses the margin formula, so the target percentage is a share of the final price.
Your cost definition matters
Accounting measures differ depending on which expenses they include. This calculator subtracts the labor, travel, supplies and overhead you enter. Its result is an estimated margin after entered costs, not a guaranteed accounting net margin.
If you discover $20 of omitted costs after pricing the job at $200, the revised $170 cost leaves $30: a 15% margin. A higher target cannot repair incomplete inputs.
Make the estimate useful
Include all applicable costs, use a target below 100%, and check the result against the agreed scope and your actual job records. The calculator accepts targets from 0% to 99%; its example percentages are not recommended industry margins.
Prices display to the nearest cent. Small rounding differences can mean the final realized percentage differs slightly from the target.
See the effect of extra labor time
Keep the hypothetical selling price at $200 and starting costs at $150. Two additional cleaner-hours at $25 each add $50 to costs. The revised cost is $200, leaving $0 profit and a 0% margin after entered costs.
To retain a 25% target margin on the revised $200 cost, the price calculation becomes $200 ÷ 0.75 = $266.67, rounded to cents.
Changing the calculator’s target does not change a price already agreed with a client. Use actual times to improve future estimates, and discuss any scope or pricing changes through your agreed process.
Sources & assumptions
Sources checked September 9, 2026. Worked examples are invented to explain the calculation; they are not industry averages or claims of firsthand operating experience.