%Free calculator

Percentage calculator

Four everyday percentage questions in one place. Pick the type of calculation, enter two numbers and see the answer and the formula instantly.

Result
—

Calculated instantly in your browser — nothing you enter is sent or stored.

Embed this calculator on your website

Free for blogs and websites: copy the code and paste it into your page (in WordPress, use a “Custom HTML” block). It works on phones and desktops, and the height adjusts automatically.

Preview

How to use the percentage calculator

Choose what you want to find out with the buttons at the top of the calculator:

  • X% of Y – for example, how much is a 15% tip on a $64 bill?
  • X is what % of Y – for example, you scored 42 out of 60. What percentage is that?
  • % change – a price went from 80 to 92. By what percentage did it rise?
  • Add / subtract % – what is 250 plus 8%, or 250 minus a 20% discount?

Type your numbers. The result updates as you type and the formula used is shown underneath, so you can check it or do it by hand next time.

The formulas

A percentage is simply a number out of 100. "Per cent" means "per hundred", so 15% is the same as 15 ÷ 100 = 0.15.

X% of Y = X ÷ 100 × Y

X as a % of Y = X ÷ Y × 100

% change = (new − old) ÷ |old| × 100

Y plus X% = Y × (1 + X ÷ 100)  ·  Y minus X% = Y × (1 − X ÷ 100)

Worked examples

A 15% tip on $64

15 ÷ 100 × 64 = $9.60. The total to pay is $64 × 1.15 = $73.60.

42 out of 60 as a percentage

42 ÷ 60 × 100 = 70%.

A price rise from 80 to 92

(92 − 80) ÷ 80 × 100 = 12 ÷ 80 × 100 = 15% increase.

A 20% discount on 250

250 × (1 − 0.20) = 250 × 0.80 = 200. You save 50.

Common mistakes

Adding and removing the same percentage does not cancel out. If a $100 item goes up 10% to $110 and then down 10%, it ends at $99, not $100 – because the second 10% is taken from the bigger number.

Percent vs percentage points. If an interest rate rises from 2% to 3%, it went up by one percentage point, but by 50 percent (1 ÷ 2 × 100).

Removing a percentage that was added. To find the original price before a 20% mark-up, divide by 1.20 – do not subtract 20%. $120 ÷ 1.20 = $100, whereas $120 − 20% = $96.

Frequently asked questions

How do I calculate a percentage of a number?
Divide the percentage by 100 and multiply by the number. 30% of 450 = 0.30 × 450 = 135.
How do I calculate the percentage increase between two numbers?
Subtract the old value from the new value, divide by the old value and multiply by 100. From 50 to 65: (65 − 50) ÷ 50 × 100 = 30%.
How do I reverse a percentage?
If a price already includes a percentage, divide by (1 + percentage ÷ 100). A price of 118 including 18% is 118 ÷ 1.18 = 100 before the increase.
Can a percentage be more than 100%?
Yes. If a value more than doubles, the increase is over 100%. Going from 20 to 50 is a 150% increase.

Last reviewed: November 13, 2026

Results are estimates for general information only and are not financial, tax, medical or legal advice. Check important figures with a qualified professional.