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  3. Percentage Calculator
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Percentage Calculator

Calculate percentages, percentage changes, increases, decreases, and find original values. Multiple calculation modes with formulas.

What is 15% of 230? What percentage is 45 of 300? How much does a price change from 80 to 100? This tool answers all three types of percentage questions with a single input form.

Runs in your browser and files never uploadedMore math & scienceJump to full guide

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Percentage Calculator: a worked example

You need three related answers fast: 15% of 240, what percent 36 is of 240, and the change from 240 to 300.

Inputs

15% of 240 · 36 is what % of 240 · 240 → 300
Percentage Calculator produces

Results

36
15%
+25% increase

The three percentage questions people constantly mix up, "of", "is what percent of", and "percent change", are handled as distinct modes so you do not have to remember which formula goes where. Each shows the calculation, not just the number.

What is Percentage Calculator?

What is 15% of 230? What percentage is 45 of 300? How much does a price change from 80 to 100? This tool answers all three types of percentage questions with a single input form.

How to use

  1. 1Choose the calculation type: percentage of a number, what percent one number is of another, or percentage change
  2. 2Enter the values and see the result instantly

Key features

  • Calculate X% of Y
  • Find what percentage X is of Y
  • Percentage increase or decrease between two values
  • Instant results as you type

Tips & best practices

  • For percentage change, enter the original value first and the new value second.
  • To reverse a percentage (find the original price before a 20% discount), divide the discounted price by 0.80.

Common use cases

  • Shopping discounts

    Figure out the sale price after a percentage-off discount.

  • Grade calculations

    Convert raw scores into percentages.

  • Financial analysis

    Compute growth rates, margin percentages, or markup values.

Private by design

Every calculation runs locally in your browser. Your numbers and expressions are not transmitted or stored.