What is 80% of 20? 16 80% of 20 Copy 80% of 20 = 16. Formula UsedResult = (80 ÷ 100) × 20 = 16 Frequently Asked Questions What is 80% of 20?16. (80 ÷ 100) × 20 = 16.How to calculate 80%?Multiply by 0.8 (or multiply by 80 then divide by 100).