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Percentage Calculator

Calculate percentages, percentage changes, and ratios with instant results. Perfect for finance, shopping, grades, and more.

Calculate X% of Y

50
25% of 200 = (25 ÷ 100) × 200 = 50

Quick Reference

10% of 100
= 10
25% of 80
= 20
50% of 200
= 100
15% of 300
= 45

🧮 Multiple Modes

Calculate basic percentages, percentage changes, and ratios with dedicated interfaces for each type of calculation.

⚡ Instant Results

See results immediately as you type with real-time calculations and helpful explanations of the math.

📚 Educational

Learn how percentage calculations work with step-by-step explanations and quick reference examples.

Complete Percentage Calculator Guide

Our percentage calculator handles all common percentage calculations with instant results and clear explanations. Perfect for students, professionals, shoppers, and anyone who needs quick percentage math.

How to Use Each Calculator Mode:

1. Basic Percentage (X% of Y)

Calculate what a percentage of a number equals. Common uses:

  • Tips: What's 20% of a $50 bill?
  • Discounts: What's 25% off $100?
  • Tax: What's 8.5% tax on $200?
  • Commission: What's 5% commission on $1000 sales?

2. Percentage Change

Calculate the percentage increase or decrease between two numbers. Common uses:

  • Price changes: Stock went from $100 to $120
  • Performance: Sales increased from 500 to 650 units
  • Growth rates: Population grew from 10,000 to 12,500
  • Grade improvement: Test score went from 75% to 85%

3. What Percentage (X is what % of Y)

Find what percentage one number represents of another. Common uses:

  • Test scores: Got 85 points out of 100 possible
  • Completion rates: Finished 75 tasks out of 100
  • Market share: Company has 250 out of 1000 customers
  • Budget allocation: Spending $300 of a $2000 budget

Percentage Formulas Reference:

Basic Percentage

Formula: (Percentage ÷ 100) × Number = Result

Example: 25% of 200 = (25 ÷ 100) × 200 = 50

Percentage Change

Formula: ((New Value - Old Value) ÷ Old Value) × 100

Example: From 100 to 120 = ((120 - 100) ÷ 100) × 100 = +20%

Ratio to Percentage

Formula: (Part ÷ Whole) × 100 = Percentage

Example: 25 out of 200 = (25 ÷ 200) × 100 = 12.5%

Common Percentage Calculations:

Shopping & Finance

  • Calculate sale discounts and final prices
  • Determine tip amounts at restaurants
  • Figure out tax amounts on purchases
  • Calculate loan interest and payments
  • Determine profit margins and markups

Academic & Testing

  • Convert test scores to percentages
  • Calculate grade point averages
  • Determine passing rates and statistics
  • Analyze survey response rates

Business & Analytics

  • Calculate growth rates and trends
  • Determine market share percentages
  • Analyze conversion rates
  • Calculate commission and bonuses
  • Measure performance improvements

Tips for Accurate Calculations:

  • Double-check your inputs for typos
  • Remember that percentages are parts of 100
  • Use decimal points for precise calculations
  • Consider rounding for practical applications
  • Verify results make sense in context