What is 3% of 30? 0.9 3% of 30 Copy 3% of 30 = 0.9. Formula UsedResult = (3 ÷ 100) × 30 = 0.9 Frequently Asked Questions What is 3% of 30?0.9. (3 ÷ 100) × 30 = 0.9.How to calculate 3%?Multiply by 0.03 (or multiply by 3 then divide by 100).