% Percentage Calculator

What is 30% of 30?

30% of 30 is 9. Use the calculator below to change either number, or see related calculations.

Enter values above to calculate.

Calculating 30% of 30: divide 30 by 100, then multiply by 30. The general formula is (X ÷ 100) × Y — works for any percentage and any number.

Percentages around this level appear in everyday calculations (interest rates, growth, splits). This base value sits in the everyday range — receipts, tips, small purchases.

How it works.

Formula: (X ÷ 100) × Y.

Step by step:

  1. Divide the percentage by 100: 30 ÷ 100 = 0.3.
  2. Multiply by the number: 0.3 × 30 = 9.
Worked examples
30% of 30 = 9 — the basic calculation: divide 30 by 100 (= 0.3), then multiply by 30.
30% of 30 as a tip on a small bill — if a service charge of 30% is added to a 30 item, the extra is 9.
30% off a 30-pound item — the discount saves 9; the sale price is £21.
Related: 28% of 30 33% of 30 30% of 25 30% of 40 X% of Y calculator

Frequently asked questions

How do I calculate 30% of 30?
Divide 30 by 100, then multiply by 30. 30 ÷ 100 = 0.3; 0.3 × 30 = 9. The same formula works for any pair of numbers.
What is 30 percent of 30?
9. The full calculation: (30 ÷ 100) × 30 = 0.3 × 30 = 9.
What's the formula for any percentage of any number?
Divide the percentage by 100 to convert it to a decimal, then multiply by the number. The general formula is (X ÷ 100) × Y. The percentage calculator above uses this for any pair of values; results display to 4 decimal places.