Converters.net

Percentage Calculator

Use our free online tool to calculate percentages of numbers or percentage increases & decreases instantly.

Percentage Calculator

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What is percent of ?
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Result
is what percent of ?
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Result
What is the percentage increase/decrease from to ?
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Result
Enter numbers in the input boxes and your answer will be automatically calculated.

Percentage Calculator — Fast, Accurate & Free

Use this Percentage Calculator to compute percentages instantly — find x% of y, determine what percent one number is of another, or calculate percentage increase/decrease. The tool is designed for accuracy, accessibility, and mobile use — ideal for students, professionals, and shoppers.

Key features

  • Instant results: real-time calculations as you type.
  • Three modes: percent of, what percent, and percentage change.
  • Copy result: copy the computed value with one click.
  • Accessible UI: large inputs, ARIA labels and keyboard support for screen readers.
How to use the Percentage Calculator

1. Select a converter

Choose one of the sentence-style inputs (for example: “What is (number) percent of (number)?”).

2. Enter your numbers

Type the values into the input fields. Placeholders show the expected input (for example: number, original, new).

3. Read or copy the answer

The Result box updates automatically. Click Copy to copy the value to your clipboard or use Calculate to force an immediate update.

Examples (quick reference)

Question Inputs Answer
What is 20% of 150? 20, 150 30
50 is what percent of 200? 50, 200 25%
Percentage change from 80 to 100 80 → 100 +25%

How the math works (concise)

  • Percent of: (p / 100) × x
  • What percent: (a / b) × 100
  • Percentage change: ((new − original) / |original|) × 100

Use cases & benefits

  • Shopping: calculate sale prices and discounts quickly.
  • Finance: measure returns and percentage changes over time.
  • Education: verify homework and illustrate percent concepts.
  • Reporting: convert ratios and fractions into percentages for presentations.

Tips

  • Enter decimal values (e.g., 12.5) for precise percentages.
  • The tool handles negative numbers and zero safely; invalid operations show a neutral placeholder.
  • To preserve formatting for spreadsheets, copy the result and paste into your sheet.

Frequently Asked Questions

Is this calculator free?

Yes — this percentage calculator is free to use directly on this page.

How precise are the results?

The tool rounds sensibly and formats outputs for readability; very large or very small values may use scientific-style formatting for clarity.

Does this work on mobile?

Yes — the UI is mobile-optimized with large input controls and touch-friendly buttons.

Get started

Try the calculator on this page — enter your numbers and view results instantly. Click here to calculate percentages.

Note: Looking for a different type of calculator? We have a huge range available at converters.net – browse our selection to find what you need.

Quick Actions

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