Enter the revenue and expense figures from your financial data. Click the Calculate button; read the net profit and the profit margin. You may click on Clear Values and do another. You MAY enter a decimal for data in the revenue and expense fields but do not enter any commas or dollar signs (, or $). Sales profit and gross profit are somewhat synamous but are different from net profit. These expenses are ONLY for sales related expense while ALL expenses are taken into account with net profit.