difference between operating profit margin and net profit margin
Net profit is the $ left over from the gross profit after deducting the overheads. Net profit margin is the net profit $ expressed as a % of the revenue. So, if net profit is $5,000 and the revenue was $30,000 then the net profit margin is ... 5,000 divided by 30,000 = 16.66%. This is a measure of the firm's overall profitability, performance and sustainability.
Operating margin is the proportion of revenues remaining after paying the costs of operating the business, such as labor costs (wages), raw materials, overhead, depreciation and amortization, selling, general, and administrative expenses, advertising, etc.