The net profit margin is a financial ratio that measures the profitability of a company. It is calculated by dividing the company's net income by its total revenue, and is expressed as a percentage. The net profit margin indicates how much of every dollar of revenue the company is able to keep as profit after all expenses have been paid. A high net profit margin indicates that the company is able to generate a lot of profit from its sales, while a low net profit margin indicates that the company is not very profitable.