Percentage Calculator

Formula used

X% of Y = (X ÷ 100) × Y · X as a % of Y = (X ÷ Y) × 100 · % change = (new − old) ÷ |old| × 100

How to use this calculator

1. Choose the question you are trying to answer from the dropdown.
2. Enter the two values — the labels tell you which is which.
3. Read the steps to see the method as well as the answer.

Example calculation

What does this result mean?

The most common error is calculating percentage change against the wrong base. Going from 50 to 75 is a 50% increase, but going back from 75 to 50 is a 33.3% decrease, because the denominator changed. Percentage-point differences are different again: a rate moving from 4% to 6% is a two percentage-point rise but a 50% increase.

Frequently asked questions

How do I add a percentage to a number quickly?

Multiply by 1 plus the decimal. Adding 15% means multiplying by 1.15; removing 15% means multiplying by 0.85.

Why isn't a 50% rise cancelled by a 50% fall?

Because the second percentage applies to the larger number. 100 up 50% is 150; 150 down 50% is 75, not 100.

What is a percentage point?

The arithmetic difference between two percentages. From 4% to 6% is 2 percentage points and a 50% relative increase.

Related calculators

• Discount CalculatorSale price and savings from one or two stacked discounts.
• Average Calculator (Mean, Median, Mode)Mean, median, mode, range and totals from any list of numbers.
• Ratio CalculatorSimplify ratios, scale them, and solve for a missing term.
• Tip CalculatorTip amount, total bill and per-person share.