What is 5% of 40? 2 5% of 40 Copy 5% of 40 = 2. Formula UsedResult = (5 ÷ 100) × 40 = 2 Frequently Asked Questions What is 5% of 40?2. (5 ÷ 100) × 40 = 2.How to calculate 5%?Multiply by 0.05 (or multiply by 5 then divide by 100).