📊 Percentage Calculator

Calculate percentages, increases, decreases, and more

What percentage is X of Y?

is what % of

Common Examples

Restaurant Tip (15%)
Calculate 15% tip on a $50 bill
Sale Discount (25% off)
25% discount on $80 item
Sales Tax (8.5%)
Add 8.5% tax to $100 purchase
Test Score
85 out of 100 points = ?%

📊 Complete Guide to Using a Percentage Calculator

Master percentage calculations with our comprehensive guide

A percentage calculator is an essential tool for calculating percentages, discounts, increases, decreases, and more. Whether you're shopping for deals, calculating tips, analyzing data, or working on homework, our online percentage calculator provides instant, accurate results right in your browser.

🎯 What is a Percentage Calculator?

A percentage calculator is a tool that performs various percentage-related calculations. It can find what percentage one number is of another, calculate percentage increases or decreases, find the value after a percentage change, and more. This eliminates manual calculations and reduces errors.

💡 Why Use an Online Percentage Calculator?

Our online percentage calculator offers several advantages: instant calculations for multiple percentage types, handles discounts, tips, taxes, and increases, works on all devices, and requires no installation. Perfect for shopping, finance, homework, and everyday calculations!

🏃 Common Uses for a Percentage Calculator

🛍️
Shopping & Discounts
Calculate sale prices and savings. Find final price after discounts and determine how much you save.
💰
Tips & Service Charges
Calculate restaurant tips quickly. Determine 15%, 18%, or 20% tip amounts instantly.
📈
Finance & Investments
Calculate interest rates, returns, and growth. Analyze percentage changes in stocks and investments.
🎓
Grades & Test Scores
Convert scores to percentages. Calculate what percentage you scored on tests and assignments.
📊
Business & Analytics
Calculate growth rates, profit margins, and KPIs. Analyze business metrics and performance.
🏋️
Health & Fitness
Track weight loss/gain percentages. Calculate body fat percentage and progress metrics.

📖 How to Use Our Percentage Calculator

Our calculator offers multiple calculation modes:

Basic Percentage (X is what % of Y?)

  1. Enter the part (X) - the smaller number
  2. Enter the whole (Y) - the total or larger number
  3. See the percentage result instantly
  4. Example: 25 is what % of 100? Answer: 25%

Percentage Increase/Decrease

  1. Enter the original value
  2. Enter the new value
  3. See the percentage change (increase or decrease)
  4. Example: From 50 to 75 = 50% increase

What is X% of Y?

  1. Enter the percentage (X%)
  2. Enter the number (Y)
  3. See the calculated value
  4. Example: What is 20% of 150? Answer: 30
🛍️ Example: Shopping Discount

Scenario: A $80 item is on sale for 25% off. What's the final price?

Solution: 25% of $80 = $20 discount. Final price = $80 - $20 = $60. You save $20!

⚡ Pro Tips for Percentage Calculations

1
Quick Mental Math
10% is easy - just move decimal left once. 50% is half. 25% is a quarter. Use these for quick estimates!
2
Tip Calculation Trick
For 20% tip: Find 10% (move decimal), then double it. For 15%: Find 10%, then add half of that.
3
Discount Stacking
Two 20% discounts ≠ 40% off! Apply each separately: 20% off $100 = $80, then 20% off $80 = $64 (36% total).
4
Percentage vs Points
Percentage change vs percentage points are different. From 20% to 25% is a 5 percentage point increase, but a 25% relative increase.

🔑 Key Features

  • Multiple Calculators: Basic %, increase/decrease, X% of Y, and more.
  • Instant Results: Calculations appear immediately as you type.
  • Quick Examples: One-click example buttons for common calculations.
  • Clear Explanations: See how the calculation is performed.
  • Tabbed Interface: Easy switching between calculation types.
  • Mobile Friendly: Works perfectly on all devices.
  • No Installation: Works directly in your browser.
  • Always Free: No subscriptions or hidden fees.
  • Accurate: Precise calculations every time.
  • Fast: Instant results without delays.

💪 Benefits of Using a Percentage Calculator

Having a reliable percentage calculator offers numerous advantages:

🎯 Eliminate Calculation Errors

Manual percentage calculations are error-prone, especially with decimals. Our calculator ensures accuracy every time, helping you make informed decisions about purchases, finances, and more.

  • Save Time: Instant calculations instead of manual math.
  • Save Money: Quickly compare discounts and deals.
  • Make Better Decisions: Understand true costs and savings.
  • Academic Success: Complete homework accurately.
  • Professional Tool: Suitable for business and finance.
  • Always Available: Access from any device.
  • Learn Math: Understand percentage relationships.

🎓 Understanding Percentages

What is a Percentage?

A percentage is a way of expressing a number as a fraction of 100. The word "percent" means "per hundred." So 25% means 25 per 100, or 25/100, or 0.25.

Common Percentage Formulas

  • Basic Percentage: (Part ÷ Whole) × 100 = Percentage
  • Find the Part: (Percentage ÷ 100) × Whole = Part
  • Percentage Increase: ((New - Old) ÷ Old) × 100
  • Percentage Decrease: ((Old - New) ÷ Old) × 100
  • Final Value After Increase: Original × (1 + Percentage/100)
  • Final Value After Decrease: Original × (1 - Percentage/100)

Common Percentage Conversions

  • 100% = 1 (the whole)
  • 50% = 0.5 (half)
  • 25% = 0.25 (quarter)
  • 10% = 0.1 (tenth)
  • 1% = 0.01 (hundredth)
💰 Real-World Example: Restaurant Tip

Situation: Your meal costs $45 and you want to leave a 20% tip.

Solution: 20% of $45 = $9. Total bill = $45 + $9 = $54!

❓ Frequently Asked Questions (FAQ)

How do I calculate a percentage?
To find what percentage X is of Y, divide X by Y and multiply by 100. For example: 20 is what % of 80? (20 ÷ 80) × 100 = 25%.
How do I calculate a discount?
Multiply the original price by the discount percentage, then subtract from the original. Example: 30% off $100 = $100 - ($100 × 0.30) = $100 - $30 = $70.
How do I calculate percentage increase?
Subtract the old value from the new value, divide by the old value, and multiply by 100. Example: From 50 to 60 = ((60-50) ÷ 50) × 100 = 20% increase.
What's the difference between percentage and percentage points?
Percentage points measure absolute change, while percentage measures relative change. From 20% to 25% is a 5 percentage point increase, but a 25% relative increase.
How do I calculate a tip quickly?
For 20% tip: Move decimal left once (10%), then double it. For 15% tip: Find 10%, then add half of that. Example: $40 bill → 10% = $4, 20% = $8.
Can percentages be over 100%?
Yes! Percentages over 100% indicate a value greater than the whole. For example, 150% means 1.5 times the original, or a 50% increase.
How do I convert a percentage to a decimal?
Divide the percentage by 100. Example: 25% = 25 ÷ 100 = 0.25. Or simply move the decimal point two places left.
Will this work on my phone?
Yes! The percentage calculator is fully responsive and works perfectly on smartphones and tablets. All features are available on mobile devices.
How do I calculate my test grade?
Divide your score by the total points and multiply by 100. Example: 85 out of 100 = (85 ÷ 100) × 100 = 85%.
Can I calculate multiple discounts?
Yes, but apply them sequentially, not additively. Two 20% discounts don't equal 40% off. Apply the first discount, then apply the second to the new price.

🚀 Getting Started

Ready to calculate percentages? Scroll back up and choose your calculation type! Use the tabs to switch between different percentage calculations. Try the quick example buttons to see how each calculator works.

🎯 Quick Start Tips

  • Choose the right calculator tab for your needs
  • Click example buttons to see sample calculations
  • Enter your numbers and see instant results
  • Use for shopping, tips, grades, and finance
  • Bookmark for quick access anytime

📊 Conclusion

A percentage calculator is an indispensable tool for everyday life, from shopping and dining to finance and academics. Our free online percentage calculator eliminates the guesswork and errors of manual calculations, providing instant, accurate results for all your percentage needs.

Whether you're calculating discounts, tips, test scores, or business metrics, our percentage calculator provides the accuracy and ease of use you need to make informed decisions quickly and confidently.

Start calculating percentages now and never struggle with percentage math again!