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Operating Margin Calculator
Operating margin measures how much profit a business makes from its core operations, before interest and tax distort the picture. It is operating income divided by revenue, where operating income is revenue minus the cost of goods sold minus operating expenses (rent, payroll, marketing and the like). It sits between gross margin (which subtracts only COGS) and net margin (which also subtracts interest and tax), and it is the ratio analysts reach for when comparing the operational efficiency of two companies on a like-for-like basis. On revenue of $50 with $30 COGS and $10 of operating expenses, operating income is $10 and the operating margin is 20%. Most simple margin calculators only model gross margin; this mode takes the right inputs to compute operating margin directly. Free, no login.
Operating margin = operating income / revenue
- Operating income = revenue − COGS − operating expenses (before interest and tax)
- Sits between gross margin (COGS only) and net margin (COGS + opex + interest + tax)
- Worked example — revenue $50, COGS $30, opex $10: operating income $10 → operating margin 20%
- Worked example — revenue $50, COGS $30, opex $5: operating income $15 → operating margin 30%
- Best ratio for comparing operational efficiency across companies before financing and tax
- Excludes interest and tax by design — those belong to net margin, not operating margin
Frequently asked questions
What is operating margin and how is it calculated?
Operating margin is operating income divided by revenue. Operating income (also called operating profit or EBIT) is revenue minus the cost of goods sold minus operating expenses such as rent, salaries and marketing — but before interest and tax. With revenue of $50, COGS of $30 and operating expenses of $10, operating income is $10 and the operating margin is 10 / 50 = 20%. It shows how profitable the core business is at running its operations, independent of how it is financed or taxed.
How is operating margin different from gross and net margin?
The three differ by how many cost layers they subtract. Gross margin subtracts only COGS: (revenue − COGS) / revenue. Operating margin also subtracts operating expenses: operating income / revenue. Net margin additionally subtracts interest and tax: net profit / revenue. So for the same company, gross ≥ operating ≥ net. Operating margin is the middle layer — it captures the efficiency of core operations while excluding financing and tax effects, which makes it the cleanest cross-company comparison of operational profitability.
Why does operating margin exclude interest and tax?
Because interest and tax reflect a company's financing structure and jurisdiction, not how well it runs its operations. Two firms with identical operations can report very different net margins simply because one carries more debt or faces a higher tax rate. By stopping at operating income — before interest and tax — operating margin isolates operational performance, letting you compare businesses on a like-for-like basis. Interest and tax are then captured further down, in net margin.