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Percentage Calculator

Percentage Calculator — Free percentage calculator. Find what percent of a number is, calculate what percentage one number is of another, or get the percentage change between two values. Results update as you type. No signup required.

% of

Enter values above to see the result

The three percentage calculations everyone needs

  • X% of Y — the most common. “What is 20% of $85?” Used for tips, discounts, tax, commission.
  • X is what % of Y — proportion. “30 out of 120 is what percent?” Used for test scores, survey results, market share.
  • % change from X to Y — growth or decline. “Price went from $40 to $52 — what's the increase?” Used for price changes, revenue growth, weight loss, analytics.

Percentage formulas

  • X% of YResult = (X ÷ 100) × Y
  • X is what % of YResult = (X ÷ Y) × 100
  • % change from X to YResult = ((Y − X) ÷ |X|) × 100

Quick examples

  • 15% tip on $60 → 15% of 60 = $9.00
  • Score: 42 out of 56 → 42 is what % of 56 = 75%
  • Price: $120 → $90 → % change = −25% (decrease)
  • Monthly users: 8,400 → 11,200 → % change = +33.33% (increase)

Frequently Asked Questions

How do I calculate what percent of a number something is?

Use the "What % is X of Y?" mode. Enter your part (X) and your total (Y) — the tool shows the percentage. For example: 25 is what % of 200? Answer: 12.5%.

How do I calculate a percentage of a number?

Use the "X% of Y" mode. Enter the percentage and the total. For example: 15% of 80 = 12.

How do I calculate percentage change?

Use the "% change from X to Y" mode. Enter the starting value and the ending value. The tool shows the percentage increase or decrease. For example: from 50 to 75 = 50% increase.

What is the formula for percentage change?

Percentage change = ((New Value − Old Value) / |Old Value|) × 100. A positive result is an increase; negative is a decrease.

Can I calculate a percentage decrease?

Yes. Use the "% change" mode. If the new value is lower than the starting value, the tool automatically shows a decrease with a negative percentage.

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