Free Percentage Calculator – Calculate %, Increase, Decrease & Change

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Percentage Calculator Tool
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Percentage Calculator

Calculate percentages, increase, decrease, and percentage difference instantly

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💡 Common Examples:

🛍️ Shopping: 20% off $50 = $10 discount
💰 Tips: 15% of $80 bill = $12 tip
📊 Grades: 85% of 100 points = 85 points
📱 Tax: 8% sales tax on $100 = $8
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💡 Common Examples:

💼 Salary: $50,000 + 5% raise = $52,500
🏠 Real Estate: $300,000 + 10% appreciation = $330,000
📈 Investment: $1,000 + 15% return = $1,150
💵 Inflation: $100 + 3% inflation = $103
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💡 Common Examples:

🏷️ Sale: $200 – 30% off = $140
🚗 Depreciation: $25,000 car – 20% = $20,000
⚖️ Weight Loss: 180 lbs – 10% = 162 lbs
💸 Discount: $50 – 15% = $42.50
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💡 Common Examples:

📈 Stock: $50 to $60 = +20% gain
🏋️ Fitness: 200 lbs to 180 lbs = -10% loss
💰 Revenue: $1M to $1.2M = +20% growth
🎓 Grade: 70% to 85% = +21.43% improvement
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💡 Common Examples:

⚖️ Compare Prices: $80 vs $100 = 22.22% difference
📊 Test Scores: 85 vs 95 = 11.11% difference
🏃 Times: 10 min vs 12 min = 18.18% difference
💵 Salaries: $50K vs $60K = 18.18% difference

Free Percentage Calculator – Calculate Percentages Online

Need to calculate percentages quickly and accurately? Our free online percentage calculator handles all your percentage calculation needs—from basic percentages to increases, decreases, changes, and differences. Whether you’re calculating discounts, tips, grades, taxes, or financial growth, our tool provides instant, accurate results.

Understanding percentages is essential in daily life, from shopping discounts to financial planning, academic grades to business metrics. Our calculator simplifies complex percentage calculations with five specialized calculators in one tool, complete with real-time results and practical examples.

🎯 5 Calculators in One

Basic percentage, increase, decrease, change, and difference—all in one place.

⚡ Instant Results

Real-time calculations as you type. No “calculate” button needed.

💡 Practical Examples

See real-world examples for each calculation type to understand applications.

📱 Mobile Friendly

Works perfectly on all devices—desktop, tablet, or smartphone.

How to Use the Percentage Calculator

1. Basic Percentage Calculator

Use when: You need to find what percentage one number is of another.

Formula: (Percentage ÷ 100) × Number = Result

Example: What is 25% of 200? Answer: 50

Result = (Percent × Number) ÷ 100
Enter the percentage and the number to find the result

Common Uses:

  • Calculate sales tax on purchases
  • Determine restaurant tips (15%, 18%, 20%)
  • Find discount amounts during sales
  • Calculate commission earnings
  • Compute test scores and grades

2. Percentage Increase Calculator

Use when: You need to add a percentage to a number.

Formula: Number × (1 + Percentage/100) = New Value

Example: Increase 100 by 20% = 120

New Value = Number + (Number × Percent ÷ 100)
Add a percentage to find the increased value

Common Uses:

  • Calculate salary raises and bonuses
  • Determine price after adding sales tax
  • Project investment returns
  • Estimate inflation adjustments
  • Calculate markup on products

3. Percentage Decrease Calculator

Use when: You need to subtract a percentage from a number.

Formula: Number × (1 – Percentage/100) = New Value

Example: Decrease 100 by 25% = 75

New Value = Number – (Number × Percent ÷ 100)
Subtract a percentage to find the decreased value

Common Uses:

  • Calculate sale prices and discounts
  • Determine depreciation on assets
  • Track weight loss progress
  • Calculate tax deductions
  • Estimate cost reductions

4. Percentage Change Calculator

Use when: You need to find the percentage change between two values.

Formula: ((New Value – Old Value) ÷ Old Value) × 100 = % Change

Example: From 80 to 100 = +25% increase

% Change = ((New – Old) ÷ Old) × 100
Calculate the percentage increase or decrease between two values

Common Uses:

  • Track stock price changes
  • Measure business revenue growth
  • Calculate grade improvements
  • Monitor weight loss or gain
  • Analyze year-over-year changes

5. Percentage Difference Calculator

Use when: You need to compare two values relative to their average.

Formula: (|Value1 – Value2| ÷ Average) × 100 = % Difference

Example: Difference between 80 and 100 = 22.22%

% Difference = (|V1 – V2| ÷ ((V1 + V2) ÷ 2)) × 100
Compare two values relative to their average

Common Uses:

  • Compare prices from different stores
  • Analyze test score variations
  • Compare product specifications
  • Evaluate performance metrics
  • Statistical analysis and research

Understanding Percentage Formulas

What is a Percentage?

A percentage is a way of expressing a number as a fraction of 100. The word “percent” literally means “per hundred.” When you see 25%, it means 25 per 100, or 25/100, or 0.25 as a decimal.

Converting Between Decimals and Percentages

Decimal to Percentage: Multiply by 100 and add the % symbol

  • 0.25 = 25%
  • 0.75 = 75%
  • 1.5 = 150%
  • 0.05 = 5%

Percentage to Decimal: Divide by 100 (or move decimal point 2 places left)

  • 25% = 0.25
  • 75% = 0.75
  • 150% = 1.5
  • 5% = 0.05

Converting Between Fractions and Percentages

Fraction to Percentage: Divide numerator by denominator, multiply by 100

  • 1/4 = 0.25 = 25%
  • 3/4 = 0.75 = 75%
  • 1/2 = 0.5 = 50%
  • 1/5 = 0.2 = 20%

Percentage to Fraction: Put percentage over 100 and simplify

  • 25% = 25/100 = 1/4
  • 50% = 50/100 = 1/2
  • 75% = 75/100 = 3/4
  • 20% = 20/100 = 1/5

Percentage vs Percentage Points

Important Distinction: Percentage points measure absolute change, while percentage measures relative change.

Example: Interest rate increases from 2% to 3%:

  • Percentage Point Change: 1 percentage point (3% – 2% = 1)
  • Percentage Change: 50% increase ((3-2)/2 × 100 = 50%)

Real-World Percentage Applications

Shopping & Retail

Sales & Discounts: Store offers 30% off original price of $80. Sale price = $80 – (30% of $80) = $80 – $24 = $56

Sales Tax: Item costs $100 with 8% sales tax. Total = $100 + (8% of $100) = $100 + $8 = $108

Coupons: 20% off coupon on $50 purchase. Discount = 20% of $50 = $10. Pay $40.

Tips: Restaurant bill $75, 18% tip. Tip = 18% of $75 = $13.50. Total = $88.50

Finance & Investing

Investment Returns: Invest $10,000, earn 7% annual return. Profit = 7% of $10,000 = $700. New total = $10,700

Interest Rates: Loan $5,000 at 5% annual interest. Interest per year = 5% of $5,000 = $250

Stock Changes: Stock price $50 increases to $60. Change = ((60-50)/50) × 100 = 20% gain

Commission: Salesperson earns 5% commission on $20,000 sale. Commission = 5% of $20,000 = $1,000

Academic & Education

Test Scores: Scored 85 out of 100 points. Grade = (85/100) × 100 = 85%

GPA Calculation: Grade requirements often expressed as percentages (90-100% = A, 80-89% = B, etc.)

Grade Improvement: Score improved from 70% to 85%. Increase = ((85-70)/70) × 100 = 21.43%

Class Participation: Participation worth 20% of final grade. If you score 90% on participation, contributes 18 points to final grade.

Health & Fitness

Weight Loss: Current weight 200 lbs, goal is 10% loss. Target loss = 10% of 200 = 20 lbs. Goal weight = 180 lbs

Body Fat Percentage: Body composition expressed as percentage of total weight

Nutrition: Food labels show percentage of daily recommended values (%DV)

Exercise Progress: Increased running distance from 5 to 6 miles. Improvement = ((6-5)/5) × 100 = 20%

Business & Economics

Revenue Growth: Company revenue grew from $1M to $1.2M. Growth = ((1.2-1)/1) × 100 = 20%

Profit Margins: Product costs $50 to make, sells for $80. Profit margin = ((80-50)/80) × 100 = 37.5%

Market Share: Company has 15% market share means 15 out of every 100 customers choose them

Inflation Rate: 3% annual inflation means prices increase by 3% on average per year

Frequently Asked Questions

Q: How do I calculate what percentage one number is of another?
A: Divide the first number by the second number, then multiply by 100. For example, to find what percentage 25 is of 100: (25 ÷ 100) × 100 = 25%. Use our “Basic %” calculator for this.
Q: What’s the difference between percentage change and percentage difference?
A: Percentage change measures change from an original value (has direction – increase or decrease). Percentage difference compares two values relative to their average (always positive, no direction). Use change when one value is clearly “before” and difference when comparing two equal values.
Q: How do I calculate a percentage discount?
A: Use the Percentage Decrease calculator. Enter the original price and the discount percentage. For example, 30% off $50 = $35. The calculator shows both the discount amount ($15) and final price ($35).
Q: How do I add sales tax to a price?
A: Use the Percentage Increase calculator. Enter the pre-tax price and the tax rate. For example, $100 + 8% tax = $108. The calculator shows the tax amount and total price.
Q: What’s 15% of 80?
A: Use the Basic % calculator. Enter 15 for percentage and 80 for number. Result: 12. This is useful for calculating tips, discounts, or any percentage of a number.
Q: How do I calculate percentage increase in salary?
A: If you got a raise, use Percentage Increase. If you want to know the percentage of the raise, use Percentage Change. For example, salary increased from $50,000 to $55,000: Change = ((55000-50000)/50000) × 100 = 10% increase.
Q: Can percentages be over 100%?
A: Yes! Percentages over 100% indicate values greater than the whole. For example, 200% of 50 = 100. This commonly occurs with percentage increases—a value doubling represents a 100% increase.
Q: How do I calculate grade percentages?
A: Divide points earned by total points possible, then multiply by 100. For example, 85 points out of 100 = (85 ÷ 100) × 100 = 85%. Use the Basic % calculator or simply divide the numbers.
Q: What’s the formula for percentage?
A: Basic percentage formula: (Part ÷ Whole) × 100 = Percentage. For example, (25 ÷ 100) × 100 = 25%. All percentage calculations derive from this fundamental formula.
Q: How do I calculate compound percentages?
A: For successive percentage changes, apply each percentage separately. For example, $100 increased by 10% then decreased by 10%: Step 1: $100 + 10% = $110. Step 2: $110 – 10% = $99. Note: The result is NOT the original $100!
Q: Are all the calculators free to use?
A: Yes! All five percentage calculators are completely free with no limits, no registration, and no hidden fees. Use them as many times as needed on any device.
Q: Do you save my calculations?
A: No. All calculations happen in your browser. We never store, save, or have access to your numbers. Your calculations are completely private.

Conclusion

Our free percentage calculator makes it easy to handle all your percentage calculation needs. With five specialized calculators in one tool, you can quickly calculate basic percentages, increases, decreases, changes, and differences. Whether you’re shopping for discounts, planning finances, calculating grades, or analyzing business metrics, our tool provides instant, accurate results.

The calculator handles everything from simple percentage calculations to complex percentage changes and comparisons. Each calculator includes practical examples to help you understand when and how to use it, making percentage math accessible to everyone.

Start calculating percentages now – completely free, no signup required, and works on all devices!

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