Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Gross margin
38.00%
Gross profit
$38.00
Net margin
20.00%
Net profit
$20.00
Equivalent markup on cost
61.29%
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter revenue ($).
- 2Enter cost of goods sold ($).
- 3Enter operating expenses ($).
- 4Read your gross margin on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
Margin is profit as a share of the selling price — not of cost. Confusing margin with markup is the single most common pricing mistake in small business.
Worked example
Using the values the calculator loads with:
Inputs
- Revenue: 100 $
- Cost of goods sold: 62 $
- Operating expenses: 18 $
Results
- Gross margin: 38.00%
- Gross profit: $38.00
- Net margin: 20.00%
- Net profit: $20.00
- Equivalent markup on cost: 61.29%
What each field means
Inputs
- Revenue ($)
- The revenue used in the calculation, measured in $. Starts at 100 $ so you have a working example on load.
- Cost of goods sold ($)
- The cost of goods sold used in the calculation, measured in $. Starts at 62 $ so you have a working example on load.
- Operating expenses ($)
- The operating expenses used in the calculation, measured in $. Starts at 18 $ so you have a working example on load.
Results
- Gross margin
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gross profit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net margin
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net profit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Equivalent markup on cost
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the profit margin calculator work?
Margin is profit as a share of the selling price — not of cost. Confusing margin with markup is the single most common pricing mistake in small business. The underlying maths is: Margin % = (Revenue − Cost) ÷ Revenue × 100.
What do I need to enter?
3 values: revenue, cost of goods sold, and operating expenses. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the gross margin result mean?
It is returned as a percentage and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Profit Margin Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/margin
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/margin" target="_blank" rel="noopener">Profit Margin Calculator — RevenueLab</a> (2026).</p>
Source: [Profit Margin Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/margin) (2026).