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Percentage Calculator — Increase, Decrease & Of

Calculate percentages, percent change and ratios

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Features

  • Percent of
  • What percent
  • Percent change
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This tool runs on your device — your files and inputs never go anywhere.

How to Use Percentage Calculator

Calculate percentages, percent change and ratios No signup, and nothing gets uploaded for most use.

  1. 1

    Choose the type of calculation: what percent of X is Y, or percent change between two numbers.

  2. 2

    Enter the two numbers (for example what is 20% of 250?).

  3. 3

    The result appears instantly as you type — no button to press.

  4. 4

    Use the examples below to switch between common percentage problems.

Why you might like it

  • Nothing to upload — the work happens on your device.
  • Free with no signup, no watermarks, and no daily limits.
  • Works in any modern browser on any device — nothing to install.
  • Usually done in a few seconds, so it doesn't get in your way.
Try Percentage

Frequently Asked Questions

What is a percentage?▾

A percentage is a number or ratio expressed as a fraction of 100. For example, 15% means 15 out of 100, or 15/100. To take X% of a value, multiply the value by X and divide by 100.

How is percentage change calculated?▾

Percentage change = (new value − old value) ÷ old value × 100. A positive result is an increase and a negative result is a decrease, expressed as a percentage of the old value.

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