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Percentage Calculator

Calculate percentages instantly online. Find X% of Y, what % one number is of another, percentage change, and more — all in one tool. Free, no signup, runs entirely in your browser.

Examples:

Value A

and

Value B

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Percentage calculations appear in everyday contexts — discounts, tax rates, tip amounts, grade scores, interest rates, and statistical changes — but the specific calculation needed varies by situation. 'What is 20% of 150?', 'What percentage is 30 of 200?', and 'What is the percentage change from 80 to 95?' are three different operations that share the percentage concept but require different formulas.

The five most common percentage operations are: (1) X% of Y (e.g., a 15% tip on a $60 bill), (2) X is what % of Y (e.g., scoring 45 out of 60), (3) percentage change/increase (e.g., a stock going from $50 to $65), (4) adding a percentage (e.g., price + tax), and (5) subtracting a percentage (e.g., price after discount). Each requires a slightly different formula and a different framing of the question.

This tool handles all five percentage operations simultaneously. Enter values in any calculation row and the result appears instantly with the underlying formula displayed as a sub-label, so you can verify which operation matches your question and apply the result with confidence.

Common Use Cases

Calculating discounts and sale prices

A product is listed at $249 with a 35% discount. The discount amount is 35% of $249 = $87.15, so the sale price is $161.85. The percentage-off calculation uses the 'subtract a percentage' operation. This is the most frequent retail use case, applicable to e-commerce checkout logic, coupon validation, and price comparison.

Computing tax-inclusive totals

A restaurant bill is $78.50 before an 8.5% sales tax. Adding 8.5% gives $78.50 × 1.085 = $85.17. The 'add a percentage' operation handles this, and the formula label confirms the approach. The same calculation applies to VAT-inclusive pricing in European e-commerce where you need to display both base price and tax.

Analyzing growth and decline metrics

A SaaS dashboard shows monthly active users went from 12,400 to 14,820. The percentage increase is ((14,820 - 12,400) / 12,400) × 100 = 19.5%. The 'percentage change' operation produces this directly. The same formula applies to revenue growth, churn rate changes, load time improvements, and any before/after comparison in analytics reports.

Grading and scoring calculations

A student scores 67 points out of a possible 85. The percentage score is (67 / 85) × 100 = 78.8%. The 'X is what % of Y' operation handles this. Teachers, professors, and automated grading systems use this calculation to normalize raw scores to percentages for letter grade assignment and GPA computation.

How to Use the Percentage Calculator

  1. Enter any two numbers in the Value A and Value B fields.
  2. All five percentage calculations update instantly.
  3. Use the example presets to quickly load common scenarios.
  4. Click "Copy" next to any result to copy the value.

What Each Calculation Means