How to Calculate Profit Margin for Your Small Business
The formula is deceptively simple: (Revenue – Costs) ÷ Revenue × 100. The hard part is knowing which costs to include. Gross margin only counts production costs. Net margin counts everything. rent, salaries, marketing, taxes. Most small business owners know they're making money but can't put a precise number on it until a lender or investor asks.
Here's how to calculate all three profit margins, with real numbers from Nadia's online jewelry business doing $128K/year.
The Three Profit Margins Every Business Should Track
- Gross profit margin: Revenue minus the cost of making your product, divided by revenue. This tells you how efficiently you produce your goods.
- Operating profit margin: Revenue minus all operating costs (production, rent, salaries, marketing), divided by revenue. This tells you how efficiently you run your business.
- Net profit margin: Revenue minus everything (including taxes and interest), divided by revenue. This is the bottom line.
Nadia's Numbers (Last 12 Months)
| Amount | |
|---|---|
| Revenue | $128,000 |
| Cost of goods (materials, packaging, shipping) | $38,400 |
| Gross profit | $89,600 |
| Operating expenses (software, marketing, workspace, contractor) | $41,600 |
| Operating profit | $48,000 |
| Taxes + business loan interest | $12,800 |
| Net profit | $35,200 |
- Gross margin: $89,600 ÷ $128,000 = 70%
- Operating margin: $48,000 ÷ $128,000 = 37.5%
- Net margin: $35,200 ÷ $128,000 = 27.5%
Nadia's margins are excellent. 27.5% net margin is strong for any small business, and outstanding for e-commerce.
What Good Margins Look Like by Business Type
| Business Type | Typical Net Margin |
|---|---|
| Software / SaaS | 15–30% |
| E-commerce / online retail | 5–20% |
| Professional services | 15–25% |
| Restaurants | 3–9% |
| Retail stores | 2–5% |
Why Margins Matter More Than Revenue
Nadia's friend runs a similar online business doing $200,000 in revenue. 56% more than Nadia. But her friend's net margin is only 8% because she spends heavily on Facebook ads and influencer partnerships. Her friend takes home $16,000 in profit. Nadia takes home $35,200 on less revenue.
Revenue is vanity. Margin is sanity. Profit is reality.
Frequently Asked Questions
What is a good profit margin for a small business?
It varies by industry, but 10–20% net margin is generally considered healthy for a small business. Above 20% is excellent. Below 5% is fragile.
What's the difference between gross margin and net margin?
Gross margin only subtracts the direct cost of making your product. Net margin subtracts everything. rent, salaries, marketing, taxes, interest. Net margin is always lower and more accurate.
How often should I calculate my profit margin?
Monthly at minimum. Weekly if you're in a variable-cost business like restaurants. The sooner you spot a margin decline, the faster you can fix it.