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Percentage Calculator

Calculate percentages easily with our free online tool

What is X% of Y?

Formula: (X / 100) × Y

X is what % of Y?

Formula: (X / Y) × 100

Percentage Increase/Decrease

Formula: ((New - Original) / Original) × 100

Percentage Difference

Formula: |(V1 - V2)| / ((V1 + V2)/2) × 100

How to Use the Percentage Calculator

Our percentage calculator is designed to be simple and intuitive to use.

  • Select the type of calculation you want to perform
  • Enter your numbers in the input fields
  • Click the Calculate button to see your result
  • Use the Clear button to start a new calculation

Use the percentage-of mode for discounts and tax amounts, what-percent mode for ratios and test scores, and percentage difference when you want to compare two values symmetrically.

Common Uses for Percentage Calculations

Percentages are used in many everyday situations, from calculating discounts to understanding statistics.

  • Shopping discounts, markups, and sales tax
  • Test scores, grades, and progress tracking
  • Financial growth, losses, and interest comparisons
  • Comparing two values in reports or data summaries

Percentage Calculation Examples

Find 15% of 80

This mode is useful when you need to calculate a discount, tax amount, or commission value.

(15 / 100) × 80

Result: 12

Find what percent 30 is of 120

Use this when comparing a part to a whole, such as quiz scores or completion rates.

(30 / 120) × 100

Result: 25%

Calculate percentage increase

This mode shows how much a value has increased or decreased relative to the starting point.

((75 - 60) / 60) × 100

Result: 25% increase

Percentage Calculator FAQ

What is the difference between percentage change and percentage difference?

Percentage change compares a new value to an original value and shows increase or decrease. Percentage difference compares two values symmetrically using their average.

When should I use 'X is what percent of Y'?

Use that mode when you already know the part and the whole and want to convert the relationship into a percentage.

Why does the calculator reject some inputs?

The calculator needs valid numeric values, and some formulas also require a non-zero denominator such as the original value or the whole value.

Can I use this calculator for discounts and taxes?

Yes. The percentage-of mode is well suited for price discounts, taxes, tips, commissions, and any other fixed percentage amount.