% Percentage Calculator

What is 40% of 20?

40% of 20 is 8. Use the calculator below to change either number, or see related calculations.

Enter values above to calculate.

Calculating 40% of 20: divide 40 by 100, then multiply by 20. The general formula is (X ÷ 100) × Y — works for any percentage and any number.

Percentages at this level appear in UK income tax bands and a few business margin contexts. 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: 40 ÷ 100 = 0.4.
  2. Multiply by the number: 0.4 × 20 = 8.
Worked examples
40% of 20 = 8 — the basic calculation: divide 40 by 100 (= 0.4), then multiply by 20.
40% of 20 as a tip on a small bill — if a service charge of 40% is added to a 20 item, the extra is 8.
40% off a 20-pound item — the discount saves 8; the sale price is £12.
Related: 35% of 20 45% of 20 40% of 10 40% of 25 X% of Y calculator

Frequently asked questions

How do I calculate 40% of 20?
Divide 40 by 100, then multiply by 20. 40 ÷ 100 = 0.4; 0.4 × 20 = 8. The same formula works for any pair of numbers.
What is 40 percent of 20?
8. The full calculation: (40 ÷ 100) × 20 = 0.4 × 20 = 8.
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.