Percentage Calculator

  • What is X% of Y?
  • X is what % of Y?
  • % Change from X to Y
  • Find original value from X% change
Results
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Percentage calculations are everywhere in daily life — from sales discounts and tip amounts to interest rates and test scores. Our Percentage Calculator handles all the common percentage operations in one simple tool.

Use the dropdown to select your calculation type: find what percent one number is of another, calculate percent change between two values, or reverse a percentage to find the original amount before a markup or discount.

The "percent change" mode is particularly useful for tracking price increases, salary adjustments, stock performance, or comparing data across time periods. A positive result means growth, while negative values indicate a decrease.

Percentages are an essential tool for financial literacy — understanding how compound percentages work (like credit card interest or investment growth) is critical for making informed financial decisions.

Formula
X% of Y = (X ÷ 100) × Y | X as % of Y = (X ÷ Y) × 100 | % Change = ((Y − X) ÷ X) × 100

FAQ

How do you calculate percentage of a number?
To find X% of a number Y, multiply Y by X and divide by 100. For example: 25% of 200 = (25 × 200) ÷ 100 = 50.
How do I calculate percentage increase?
Percentage increase = ((New Value − Original Value) ÷ Original Value) × 100. A result over 100% means the new value is more than double the original.
What is the difference between percent and percentage?
Percent refers to a specific rate (e.g., "25%"), while percentage is the general concept (e.g., "a large percentage"). In everyday math, they're used interchangeably.
How do I reverse a percentage discount?
To find the original price before a discount: Original = Discounted Price ÷ (1 − Discount% ÷ 100). For example, $90 after 10% off → $90 ÷ 0.9 = $100 original.

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