What is 80% of 40? 32 80% of 40 Copy 80% of 40 = 32. Formula UsedResult = (80 ÷ 100) × 40 = 32 Frequently Asked Questions What is 80% of 40?32. (80 ÷ 100) × 40 = 32.How to calculate 80%?Multiply by 0.8 (or multiply by 80 then divide by 100).