Percent Calculator

Category: Algebra and General

- May 14, 2025

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Calculate percentages easily with this tool. Find percentages of numbers, calculate percent change, or determine what percent one number is of another.

Calculation Type

Select Calculation:

Percentage (%):

Of Number:

Display Options

Decimal Places:

Show calculation steps

About Percentages

A percentage is a number expressed as a fraction of 100. The word comes from the Latin per centum, meaning "by the hundred." Percentages are used to express how large or small one quantity is relative to another quantity.

Common Percentage Calculations

Finding a percentage of a number: Multiply the percentage by the number, then divide by 100.
Finding what percentage one number is of another: Divide the first number by the second, then multiply by 100.
Calculating percentage change: Subtract the initial value from the final value, divide by the initial value, then multiply by 100.

Applications of Percentages

Percentages are used in many fields:

Finance (interest rates, tax rates, discounts)
Statistics (probability, data analysis)
Business (profit margins, growth rates)
Science (concentration levels, efficiency ratings)
Education (test scores, grading systems)

What Is the Percent Calculator?

The Percent Calculator is a free online tool that helps you quickly and accurately solve percentage-related problems. Whether you're figuring out discounts while shopping, analyzing data changes over time, or working on school assignments, this calculator simplifies the process.

It supports three common types of percentage calculations:

Find a percentage of a number – useful for calculating discounts or tax.
Determine what percent one number is of another – ideal for comparisons or statistical insights.
Calculate percentage increase or decrease – handy for tracking price changes or performance improvements.

Formulas Used

1. Percentage of a number:
\[(\text{Percentage} \times \text{Number}) \div 100\]

2. What percent one number is of another:
\[(\text{Part} \div \text{Whole}) \times 100\]

3. Percent Change:
\[\left((\text{Final Value} - \text{Initial Value}) \div |\text{Initial Value}|\right) \times 100\]

How to Use the Percent Calculator

Follow these simple steps to perform your calculation:

Select the type of percentage calculation from the dropdown.
Enter the numbers in the appropriate fields.
Choose how many decimal places you'd like the result to be displayed.
Click Calculate to see the result instantly.
Optionally, check the box to see the full calculation steps and the formula used.

Why Use This Calculator?

This tool is designed for everyday usability. It's especially helpful for:

Students learning how to calculate percentages and understand percentage breakdowns.
Professionals managing finances or reports involving percent change.
Anyone looking to make quick, accurate percent calculations without manual math.

Examples of Use

Want to find 20% of $150? Use the “Find a percentage of a number” option.
Wondering what percent 30 is of 200? Choose “What percent is one number of another.”
Need to calculate the percentage increase from 120 to 180? Use the “Percent increase/decrease” function.

Frequently Asked Questions

Can this calculator help with percent error?

While it’s not a dedicated Percent Error Calculator, you can still apply the standard percent error formula manually by selecting the right option and entering observed vs. expected values. For full guidance, explore resources on how to calculate percent error and follow proper percent error steps.

Is this the same as a Scientific Calculator?

This tool focuses on percent calculations. For scientific functions, complex math tools like a Scientific Calculator or trigonometric solver are better suited for advanced operations.

Can I use this to convert percent to decimals or fractions?

No, but for that purpose, try a Percent to Decimal Calculator or Percent to Fraction Calculator to easily switch between formats.

Can I track growth with this?

Yes. If you're monitoring trends, the percent change feature acts like a Percentage Increase Calculator or Percentage Change Calculator, showing growth or reduction clearly.

More Helpful Tools

If you're working with different math needs, check out these related tools:

Fraction Calculator – for adding, subtracting, or simplifying fractions.
Exponent Calculator – for solving exponential equations.
Rounding Calculator – to round numbers quickly and accurately.
Decimal to Percent Calculator – convert decimals into percentages instantly.
Matrix Calculator – a great matrix solver for those handling Linear Algebra problems.

Whether you're tackling basic math or exploring Other tools like a Ratio Calculator, Log Calculator, or Absolute Value Calculator, finding the right calculator can save you time and improve accuracy.