What does "dollars kept per $100" mean?
A margin is a profit figure divided by sales. The SEC's guide says operating margin shows, for each dollar of sales, what percentage was profit.[S1]
So a percentage margin reads directly as dollars per $100 of sales. That makes companies of very different sizes easier to put side by side.
What are gross, operating and net margin?
All three share the same bottom number, sales. They differ in how many costs have come out of the top number.
- Gross margin uses gross profit: sales minus the cost of sales.[S1] Nvidia's earnings release, for one, reports it as a percentage.[S3]
- Operating margin uses operating profit: gross profit minus operating expenses, before interest and income tax.[S1]
- Net margin uses net profit: the bottom line, after income tax.[S1]
The SEC's guide gives the operating margin formula only.[S1] Gross and net margin use the same arithmetic: gross profit ÷ sales, and net profit ÷ sales.
One wording trap: the SEC's guide uses "gross margin" as another name for the gross profit subtotal, in dollars.[S1] So check whether a figure is dollars or a percentage.
Here is how the three are built for Amazon, each input with its own period:
- Gross margin: net sales minus cost of sales, then ÷ net sales. The inputs are $716.9B (FY2025) and $356.4B (FY2025).
- Operating margin: operating income ÷ net sales. The inputs are $80.0B (FY2025) and $716.9B (FY2025).
- Net margin: 10.8% (FY2025)
Amazon's income statement has no gross profit line, so its gross margin has to be worked out this way.[S2]
A company with a net loss has a negative net margin. The list below is A–Z, not a ranking.
See it in real companies
Net profit margin at companies on Cityfort
5 companies on Cityfort, listed A–Z (not ranked).
From each company's filings, as cited on its Cityfort stock page. These figures change when a stock page is updated.
How do you compare margins between companies fairly?
A margin is a description, not a verdict. Cityfort does not label any margin as good or bad, but a comparison only means something when these match:
The same measure. A margin measured before depreciation differs from one measured after it. Operating profit comes after depreciation.[S1]
Adjusted margins differ again, as non-GAAP measures explains.
The same period. Each live figure above names its fiscal year, and those years can end in different months. Read fiscal years that do not end in December to see why that matters.
The same kind of business. A company that resells goods has to buy them first. Amazon's cost of sales, for example, is mainly the price of the products and shipping.[S2]
The same treatment of unusual items. Net margin includes items outside the main business, such as gains on investments.[S2] Operating margin leaves them out.
Revenue, profit and cash flow walks through this with Amazon's filing.
The same bottom number. Cityfort's "$100" breakdown on Amazon's stock page divides by all money that came in, including other income. Net margin divides by sales alone, so the two can differ.