Percentage Calculator.

Use this free percentage calculator to work out what percentage of a number, what percent one value is of another, or the percentage increase or decrease between two numbers.

Percentage Calculator

What is % of ?
is what percent of ?
%
What is the percentage change from to ?
%

What Is a Percentage Calculator?

A percentage calculator is a simple tool that helps you calculate percentages quickly and accurately. Whether you need to find X% of a number, determine what percentage one number is of another, or calculate a percentage increase or decrease, this calculator gives you instant results without manual formulas.

Percentages are commonly used in finance, education, retail discounts, salary calculations, statistics, and everyday problem-solving, making this one of the most useful calculators online.

How to Use the Percentage Calculator

Using the calculator is straightforward. Choose the calculation you need, enter your values, and click calculate.

Calculate X% of Y

  1. Enter the percentage value (X).
  2. Enter the number you want to calculate the percentage of (Y).
  3. Click Calculate to see the result instantly.

Calculate What Percentage X Is of Y

  1. Enter the smaller number (X).
  2. Enter the larger number (Y).
  3. Click Calculate to see the percentage result.

Calculate Percentage Increase or Decrease

  1. Enter the original value (A).
  2. Enter the new value (B).
  3. Click Calculate to see the percentage change.

Percentage Formulas Used

This calculator uses standard, widely accepted percentage formulas:

Percentage of a Number

(X ÷ 100) × Y

What Percent One Number Is of Another

(X ÷ Y) × 100

Percentage Increase or Decrease

((New − Original) ÷ Original) × 100

These formulas ensure accurate and consistent results every time.

Percentage Calculation Examples

Example 1: What is 20% of 150?

(20 ÷ 100) × 150 = 30

Example 2: 30 is what percentage of 200?

(30 ÷ 200) × 100 = 15%

Example 3: Percentage increase from 80 to 100

((100 − 80) ÷ 80) × 100 = 25% increase

When Should You Use a Percentage Calculator?

A percentage calculator is useful for:

  • Working out discounts and sale prices
  • Calculating pay rises or salary changes
  • Comparing financial growth or losses
  • Understanding test scores and grades
  • Analysing data and statistics
  • Budgeting and cost comparisons

This makes percentage calculations relevant for students, professionals, businesses, and everyday use.

Frequently Asked Questions (FAQ)

How do I calculate a percentage?

Divide the percentage by 100, then multiply by the number. For example, 10% of 200 is (10 ÷ 100) × 200.

How do I calculate a percentage increase?

Subtract the original value from the new value, divide by the original value, then multiply by 100.

How do I calculate the percentage decrease?

Subtract the new value from the original value, divide by the original value, then multiply by 100.

Can I use this calculator for financial calculations?

Yes. This calculator is widely used for discounts, salary changes, interest comparisons, and general financial analysis.

Related Calculators