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HomeCalculatorsPercentage Calculator

Percentage Calculator — 3 Modes Free Online

Calculate percentages with three modes: X% of Y, X is what % of Y, and percentage change.

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How to Use

  1. 1Choose a mode: 'X% of Y' to find a percentage of a number (e.g., 20% of $150 = $30), 'X is what % of Y' to find the rate (e.g., 45 out of 60 = 75%), or 'Percentage Change' to compare two values (e.g., $80 → $96 = +20%).
  2. 2Enter the two required values for the selected mode. For Percentage Change, enter the original value first and the new value second.
  3. 3Read the result instantly — it updates as you type, no button needed.
  4. 4Use the quick-fill presets to load a common scenario (like a tip calculation or grade percentage) as an example you can modify.
  5. 5Click Copy to save the result, or switch modes without losing your numbers — the inputs carry over when applicable.

About Percentage Calculator

The Percentage Calculator handles three essential calculation modes: find what X% of Y equals, determine what percentage X is of Y, and calculate the percentage change between two values. Quick-fill examples make common scenarios one click away.

Use it for discounts (What is 20% of $150?), grades (85 out of 100 is what %?), financial comparisons (percentage change from $50 to $65), and any daily calculation involving percentages.

All calculations run locally in your browser. The tool supports decimal inputs, negative values (for losses and decreases), and displays results with consistent formatting ready for reports and presentations.

Frequently Asked Questions

What calculation modes are available?

Three modes: find X% of a number (e.g., 20% of 150), find what percentage X is of Y (e.g., 30 is what % of 200), and percentage change between two values.

How is percentage change calculated?

Percentage change = ((New Value − Old Value) / Old Value) × 100. A positive result means increase, negative means decrease.

Does it handle decimals and negative numbers?

Yes. Decimal inputs are supported in all modes, and negative values work for losses, declines, and signed comparisons.

Can I use this for calculating discounts?

Yes. Use the 'X% of Y' mode. For example, to find a 25% discount on $80, calculate 25% of 80 = $20 off.

What are the quick-fill examples?

Pre-configured common scenarios (like tip calculations, grade percentages, and price changes) that auto-fill the inputs so you can see results instantly.

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