Percentage Calculator
Work out what X percent of a number is — useful for tips, tax and discounts.
Percentage formula
"X percent of Y" is (X ÷ 100) × Y. For example, 15% of 200 = (15 ÷ 100) × 200 = 30.
Common uses
The same formula handles a 20% tip on a $50 meal ($10), an 8% sales tax on a $200 purchase ($16), or a 30% discount on a $90 item ($27 off). For increase/decrease between two numbers see the percentage change calculator.
FAQ
How do I reverse it — what percent is A of B?
Divide A by B and multiply by 100. For example, 30 out of 200 is (30 ÷ 200) × 100 = 15%.