The three margins answer three different questions
Gross margin asks whether the product itself makes money. It subtracts only what the goods cost to make or buy, so a low figure means volume will not rescue it: the structure of the business is the problem. A software company at 80% and a distributor at 20% are not well and badly run, they are differently shaped.
Operating margin is what survives the cost of running the company — research, marketing, head office. A wide gross margin with a thin operating margin says the product earns its keep but selling it does not come cheap. That pattern is common in a company still buying its growth, and it is not by itself a bad sign.
Net margin is what is left after interest, tax and everything unrelated to operations. It is the most complete figure and the least stable one: a one-off gain on an asset sale, a currency swing or a legal settlement all land here. A single year of it is a poor guide to how profitable a company actually is.
Read the gap between operating and net income
This calculator also shows operating income minus net income, because what sits in that gap says a good deal about the company. If it is 20–30% of operating income and roughly the same every year, it is mostly tax. That is unremarkable.
But if the gap exceeds half of operating income, or moves sharply year to year, it is worth chasing down. Heavy interest on borrowings, currency movements on foreign sales, or equity-method results from affiliates all show up there. Any of them is found in the notes rather than on the face of the statement, and none of them necessarily repeats in the same direction next year.
Net income is sometimes larger than operating income — a gain on a disposal, a tax credit, something from outside the business. Reading the improved net margin as improved profitability gets it exactly backwards.
Margins do not compare across industries
The page places your operating margin among fifty collected companies. A ratio carries no currency, so Korean and US filers sit on one axis with nothing converted. But that distribution mixes industries: a semiconductor maker and a retailer are in the same row.
So read the percentile as "is this figure ordinary among listed companies" rather than "is this company doing well". For a like-for-like comparison, pick companies in the same sector and run their own reported figures through this tool.