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Percentage Calculator

Calculate percentages, percent change, and ratios

Percentage Calculator is a free online tool from BrowserUtils that calculate percentages, percent change, and ratios. It runs entirely in your browser — your data never leaves your device. No account required.

How to use Percentage Calculator

  1. 1 Paste or type your input into the editor above.
  2. 2 The tool processes your data instantly — right in your browser, with nothing sent to a server.
  3. 3 Copy the result with one click or continue editing your input.

About Percentage Calculator

Free online percentage calculator. Calculate X% of Y, find what percent X is of Y, and compute percentage change between two values. This tool runs entirely in your browser — your data is never sent to a server. Just paste your input, get instant results, and copy with one click. No sign-up or installation required.

Percentage Calculator specs

Runtime
100% client-side (browser)
Cost
Free — no account, no rate limits, no usage caps
Browser support
Chrome 90+, Firefox 88+, Safari 14+, Edge 90+
Part of
299 developer tools on BrowserUtils (100% client-side)

Questions

How do I calculate what percent X is of Y?
Divide X by Y and multiply by 100. For example, 25 is 50% of 50 because (25 / 50) × 100 = 50%.
How is percentage change calculated?
Percentage change = ((New − Old) / |Old|) × 100. A positive result means an increase, a negative result means a decrease.
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is (150 × 20) / 100 = 30. This calculator handles all three common percentage operations for you.
What is the difference between percentage change and percentage difference?
Percentage change measures the increase or decrease from an original value to a new value. Percentage difference compares two values without treating either as the "original," using their average as the denominator.
Does this percentage calculator work offline?
Yes. All calculations run in your browser using JavaScript. No data is sent to a server, and the tool works without an internet connection after the page loads.
Embed this tool

Copy this code to embed the tool on your website. Adjust the height to fit your layout.

<iframe src="https://www.browserutils.dev/embed/percentage-calculator" width="100%" height="500" frameborder="0" title="Percentage Calculator"></iframe>

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