Free Online Percentage Calculator | Find Percentages

Whether you're calculating a discount, figuring out a tip, or analyzing a change in data, percentages are a part of everyday life. Our Free Online Percentage Calculator is a collection of simple tools designed to take the guesswork out of your percentage problems, giving you quick and accurate answers instantly.

Online Percentage Calculator Tool 25% Percentage Calculator

Live Percentage Calculator

What is X% of Y?

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X is what percent of Y?

Percentage Increase/Decrease

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How to Use Our Percentage Calculators

We've broken down the most common percentage problems into three simple calculators. Just find the one that matches your question and fill in the blanks.

1. What is X% of Y?

Use this to find a percentage of a number. For example, "What is 20% of 150?" The answer is 30.

2. X is what percent of Y?

Use this to find what percentage one number is of another. For example, "30 is what percent of 150?" The answer is 20%.

3. Percentage Increase/Decrease

Use this to find the percentage change between two numbers. For example, the change from 100 to 125 is a 25% increase. The change from 125 to 100 is a -20% decrease.

Everyday Examples

  • Shopping: A shirt costs $40 and is on sale for 25% off. How much is the discount? Use the first calculator: "What is 25% of 40?" Answer: $10.
  • Test Scores: You scored 45 out of a possible 60 points on a test. What is your score? Use the second calculator: "45 is what percent of 60?" Answer: 75%.
  • Business Growth: Your website traffic went from 5,000 visitors last month to 6,000 this month. What is the growth? Use the third calculator: "From 5000 to 6000?" Answer: 20% increase.

Understanding the Basic Percentage Formulas

A percentage is a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign, "%". While our calculator does the work for you, it's helpful to understand the basic math behind it.

The three calculators use these core formulas:

  1. Finding a percentage of a number: To find what X% of Y is, you convert the percentage to a decimal and multiply.
    Result = (X / 100) * Y
  2. Finding what percentage X is of Y: To find what percentage the number X is of number Y, you divide X by Y and multiply by 100.
    Result = (X / Y) * 100
  3. Finding the percentage change: To find the percentage change from an old value to a new value, you subtract the old from the new, divide by the old value, and then multiply by 100.
    Result = ((New Value - Old Value) / Old Value) * 100
    A positive result is a percentage increase, and a negative result is a percentage decrease.

Frequently Asked Questions (FAQ)

Q1: How do I calculate a percentage in reverse?

This is a common question, for example, "If $120 is the price *after* a 20% discount was applied, what was the original price?" You can't just add 20% to $120. The original price (let's call it P) was reduced by 20%, so you paid 80% of P. The formula is `P * 0.80 = 120`. To find P, you would calculate `120 / 0.80`, which equals $150.

Q2: What is the difference between percent and percentage?

In common usage, the terms are often used interchangeably. Technically, "percent" (or the % symbol) is used with a specific number (e.g., "10 percent"). "Percentage" is a more general term for a portion of a whole (e.g., "The percentage of students who passed was high.").

Q3: What does "per cent" mean?

The word "percent" comes from the Latin phrase *per centum*, which literally means "by the hundred." This is the core concept of percentages: they represent a part of a whole, where the whole is always considered to be 100.