1. Start with the same dollars
Suppose a small job has $100 in direct costs and you sell it for $125. The difference is $25. Nothing about the job changes when you switch from markup to margin; you are measuring the same $25 against a different starting point.
($125 − $100) ÷ $100 = 25%
($125 − $100) ÷ $125 = 20%
In this article, costs mean the direct job costs you have identified. The amount left is before overhead and other expenses. Use consistent cost definitions when comparing your estimates with your bookkeeping reports.
2. Use markup when adding a percentage to cost
The markup formula is straightforward: selling price = cost × (1 + markup). Write 25% as 0.25, so a 25% markup on $400 is $400 × 1.25 = $500. The $100 difference is 20% of the $500 selling price.
Markup can be a convenient way to calculate a selling price. The mistake is naming the result a 25% margin. Before copying a percentage from a colleague's estimate or an old spreadsheet, check whether it multiplies the cost or targets a share of revenue.
3. Divide by the remaining share for a target margin
For a target gross margin, use selling price = cost ÷ (1 − target margin). At a 25% target, costs must represent 75% of the selling price. With $400 of direct job costs, the calculation is $400 ÷ 0.75 = $533.33, rounded to cents.
That leaves approximately $133.33 before overhead and other expenses. It is a pricing scenario, not a recommended margin or a promise of net profit. Decide whether the dollar amount left can support your business at the volume you realistically expect.
A 100% target margin cannot produce a finite selling price for a positive cost with this formula. If a calculation errors or returns an implausible amount, check the percentage input before sending the estimate.
4. Compare percentages before using them
This table keeps direct job cost at $400. The displayed margin percentages are rounded where needed.
| Markup | Selling price | Amount above cost | Gross margin |
|---|---|---|---|
| 10% | $440 | $40 | 9.09% |
| 20% | $480 | $80 | 16.67% |
| 25% | $500 | $100 | 20% |
| 50% | $600 | $200 | 33.33% |
| 100% | $800 | $400 | 50% |
To convert a markup to margin, divide markup by one plus markup. A 50% markup gives 0.50 ÷ 1.50 = 33.33% margin. To convert margin to markup, divide margin by one minus margin. A 25% margin requires 0.25 ÷ 0.75 = 33.33% markup.
5. Check a discount in dollars
A $500 price on a $400 direct cost leaves $100. A 10% discount reduces the selling price by $50, to $450. Costs have not changed, so only $50 remains.
The discount removed half of the dollars available above direct cost. Gross margin is now $50 ÷ $450, or about 11.11%. That does not automatically make the job unacceptable, but it is a different decision from “giving up ten percent of the profit.”
If the customer needs a lower price, assess a smaller, clearly described scope. Recalculate both the costs and selling price. Removing $50 from the quote while keeping every task does not remove $50 of work.
6. Leave room for overhead and actual results
Direct costs are only part of the picture. Software, general administration and other business expenses still need funding. The SBA's break-even calculator separates fixed costs from variable costs when assessing the sales volume needed to cover costs. Its fixed/variable categories are a different view from this article's direct-job-cost examples.
Do not call gross margin take-home pay. Also check your actual job costs: a planned $400 cost becoming $450 leaves just $50 on a $500 sale, even without a discount.
The small painting job example shows how two extra labor hours change the result. Keep estimated and actual hours so you can improve the next quote.
Questions contractors ask about the formulas
Is a 30% markup the same as a 30% margin?
No. A 30% markup gives 0.30 ÷ 1.30, or about 23.08% margin. A 30% margin requires about 42.86% markup on the same cost basis.
Which one should appear on the customer estimate?
The customer primarily needs the included work and selling price. Keep your cost and percentage calculations in your internal planning unless there is a specific reason to share them.
Where do I start if my costs are incomplete?
Complete the cost sheet first. A precise percentage cannot compensate for missing labor, materials or job expenses. Use the estimate checklist before reviewing the final price.
Sources and further reading
About this article
Prepared for the Quote Your Jobs blog. Worked examples use illustrative assumptions, not customer case studies or local market rates. Replace them with the actual scope, supplier information and costs for your job.
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