Gross Margin ($) = Revenue − Cost of Goods Sold (COGS)
Gross Margin (%) = (Revenue − COGS) ÷ Revenue × 100
If you have Gross Profit and Revenue: Gross Margin (%) = Gross Profit ÷ Revenue × 100
If you have Gross Margin (%) and Revenue: Gross Profit = Revenue × (Gross Margin % ÷ 100)
If you have Gross Margin (%) and COGS: Revenue = COGS ÷ (1 − Gross Margin % ÷ 100)