Percentage Calculator

Free Percentage Calculator - Calculate Percentages Instantly

Solve any percentage problem instantly with our free online percentage calculator. Calculate what X% of a number is, find what percentage one number is of another, compute percentage increase or decrease between two values, and add or subtract percentages. Perfect for shopping discounts, restaurant tips, tax calculations, grade computation, business analytics, investment returns, and everyday math. No formulas to remember—just enter your numbers and get instant results.

Calculation Types Available

• What is X% of Y? — Find a specific percentage of any number. Example: What is 15% of 80? Answer: 12.
• X is what % of Y? — Find what percentage one number represents of another. Example: 30 is what % of 150? Answer: 20%.
• Percentage Change: — Calculate the % increase or decrease between two values. Example: From 50 to 65 = +30% increase.
• Increase/Decrease by %: — Add or subtract a percentage from a starting number. Example: 200 + 25% = 250.

Common Use Cases

• Shopping Discounts: Calculate sale prices instantly. "30% off $79.99" = $55.99 final price. Find the actual dollar amount saved.
• Restaurant Tips: Calculate 15%, 18%, or 20% tips on any bill amount. Split tips among multiple people by dividing the tip amount.
• Sales Tax: Add tax rates to prices or work backward from tax-included prices to find the pre-tax amount.
• Grade Calculations: Convert raw scores to percentage grades. Find what score you need on remaining assignments to achieve a target average.
• Business Analytics: Calculate month-over-month growth, revenue changes, cost reductions, and performance metrics.
• Investment Returns: Calculate percentage gains or losses on investments and portfolios.
• Nutritional Information: Find what percentage of daily recommended values a food contains.
• Survey Data: Convert counts to percentages for survey analysis and reporting.

Percentage Formulas Explained

• X% of Y: Multiply Y × (X / 100). Example: 20% of 150 = 150 × 0.20 = 30
• X is what % of Y: Divide (X / Y) × 100. Example: 45 is what % of 180? = (45/180) × 100 = 25%
• Percentage Change: ((New - Old) / Old) × 100. Positive = increase, negative = decrease.
• Add X% to Y: Y × (1 + X/100). Example: 500 + 10% = 500 × 1.10 = 550

Tips and Common Mistakes

• Percentage OF vs. Percentage MORE: "20% more than 100" is 120 (not 20). "20% of 100" is 20. These are different calculations.
• Percentage Change is Not Symmetric: A 50% drop followed by a 50% gain does NOT return to the original value. 100 → 50 (−50%) → 75 (+50%) = only 75, not 100.
• Converting Fractions: To convert a fraction to percentage, divide numerator by denominator and multiply by 100. 3/4 = 0.75 = 75%.

Frequently Asked Questions

What's the difference between percentage points and percent?

Percentage points measure arithmetic difference between two percentages. If interest rates rise from 3% to 5%, that's an increase of 2 percentage points (or a 66.7% increase in the rate itself). This distinction matters in finance, statistics, and journalism.

How do I calculate percentage in Excel?

Use the formula =A1/B1 and format the cell as percentage. For percentage change: =(B1-A1)/A1 formatted as percent. Our calculator does this instantly without spreadsheet setup.