Percentage Calculator
Last Updated: June 18, 2026
What is X% of Y?
Find the percentage of a number.
Enter Values to Calculate
Fill in the fields above and the result will appear instantly.
History
All calculations are performed locally in your browser. No data is uploaded or stored.
A free online percentage calculator for computing percentages, percentage increases, decreases, differences, and reverse percentages. Instant results, no sign-up.
How To Use
Follow these simple steps to get started with percentage calculator.
Enter your data
Paste or type your input into the field above.
Choose options
Select any formatting or conversion options you need.
Process instantly
Click the button to process your data in your browser.
Copy the result
Copy the output to your clipboard or download the file.
Real-World Examples
Practical situations where percentage calculator helps solve real problems.
Shopping Discounts
Calculate sale prices, discount amounts, and final costs when shopping with percentage-off deals.
Financial Planning
Compute investment returns, interest rates, salary increases, and budget allocations.
Academic Work
Calculate test scores, grade percentages, and solve percentage problems for homework.
Business Analytics
Find growth rates, market share percentages, profit margins, and revenue changes.
Why Use This Tool
Discover how this tool can improve your workflow and productivity.
Six Calculator Modes
Cover every common percentage scenario: find percentages, percentage change, difference, and reverse calculations.
Instant Results
Results update as you type with clear step-by-step breakdowns showing the formula and each calculation step.
Step-by-Step Explanations
Learn how each result is calculated with visible formulas, substitutions, and intermediate steps.
Privacy First
All calculations are performed locally in your browser. No data is ever uploaded or stored.
Common Use Cases
Practical scenarios where this tool can help you get things done.
Shopping Discounts
Calculate sale prices, discount amounts, and final costs when shopping with percentage-off deals.
Financial Planning
Compute investment returns, interest rates, salary increases, and budget allocations.
Academic Work
Calculate test scores, grade percentages, and solve percentage problems for homework.
Business Analytics
Find growth rates, market share percentages, profit margins, and revenue changes.
Health & Fitness
Track weight loss percentages, body fat percentages, and fitness goal progress.
Tool Summary
Quick facts about this tool at a glance.
What Is Percentage Calculator?
A percentage calculator is a browser-based utility that computes common percentage operations including finding a percentage of a number, determining what percent one number is of another, calculating percentage increases and decreases, percentage differences, and reverse percentages. It uses standard percentage formulas (result = percentage ÷ 100 × number) for all calculations — all processed locally in the browser without any server interaction.
About This Tool
Percentages are everywhere in daily life. Whether you are calculating a discount while shopping, figuring out your grade on a test, determining a salary increase, or computing tax on a purchase, percentages are an essential math concept. Our Percentage Calculator makes these calculations instant and error-free. With six modes covering the most common percentage scenarios, you can solve virtually any percentage problem in seconds. Every calculation includes the formula and step-by-step breakdown so you can understand how the result was reached. The tool is completely free, runs entirely in your browser, and requires no sign-up or data upload.
Quick Summary
This free percentage calculator computes percentages, percentage increases, decreases, differences, and reverse percentages entirely in your browser. Choose from six modes: what is X% of Y, X is what percent of Y, percentage increase, percentage decrease, percentage difference, and reverse percentage. Enter values to see instant results with the formula and step-by-step breakdown. Supports decimals, large numbers, and negative values where appropriate. Includes preset examples, calculation history stored locally, and one-click copy. No data is uploaded to any server.
Related Concepts
Explore related terms and topics associated with percentage calculator.
Frequently Asked Questions
Common questions about percentage calculator.
How to calculate percentage with calculator?
To calculate a percentage on our calculator, simply select the calculation mode you need (e.g., 'What is X% of Y'), enter your numbers, and the result appears instantly. For example, to find 15% of 200, enter 15 as the percentage and 200 as the number. The calculator shows the result (30) along with the formula: (15 ÷ 100) × 200 = 30.
How to calculate percentage increase?
To calculate percentage increase, subtract the original value from the new value, divide the result by the original value, and multiply by 100. For example, if a salary goes from $50,000 to $55,000: ((55,000 - 50,000) ÷ 50,000) × 100 = 10% increase. Our Percentage Increase mode does this automatically.
How to calculate percentage decrease?
To calculate percentage decrease, subtract the new value from the original value, divide by the original value, and multiply by 100. For example, if a $100 item is on sale for $80: ((100 - 80) ÷ 100) × 100 = 20% decrease. Our Percentage Decrease mode handles this instantly.
What is the percentage difference between two numbers?
Percentage difference measures the relative difference between two values. The formula is: |A - B| ÷ ((A + B) ÷ 2) × 100. For example, the difference between 100 and 150 is: |100 - 150| ÷ ((100 + 150) ÷ 2) × 100 = 50 ÷ 125 × 100 = 40%. Use our Percentage Difference mode.
How do I find the original price before a percentage increase or decrease?
Use the Reverse Percentage mode. If a price is $120 after a 20% increase, divide the current price by (1 + percentage as decimal): 120 ÷ (1 + 0.20) = 120 ÷ 1.20 = $100 (the original price). For a decrease, divide by (1 - percentage as decimal).
How to calculate a percentage of a number?
Multiply the number by the percentage divided by 100. The formula is: Result = (Percentage ÷ 100) × Number. For example, 15% of 200 = (15 ÷ 100) × 200 = 0.15 × 200 = 30. Our calculator does this instantly in the 'What is X% of Y?' mode.
What is a percentage?
A percentage is a way of expressing a number as a fraction of 100. The word 'percent' comes from the Latin 'per centum', meaning 'out of a hundred'. Percentages are denoted using the % symbol. For example, 45% means 45 out of 100, or 45/100, which equals 0.45 as a decimal.
How do you calculate grade percentage?
To calculate a grade percentage, divide the points earned by the total possible points and multiply by 100. For example, if you score 85 out of 100 on a test: (85 ÷ 100) × 100 = 85%. Use the 'X is what % of Y?' mode with your score as X and total as Y.
How to calculate discount percentage?
To find the discount percentage, divide the discount amount by the original price and multiply by 100. For example, if an item was $50 and is now $40: the discount is $10, so (10 ÷ 50) × 100 = 20% off. Use Percentage Decrease mode for automatic calculation.
How do you calculate body fat percentage?
Body fat percentage is typically calculated using skinfold measurements, bioelectrical impedance, or DEXA scans. While our percentage calculator can help with the math, body fat percentage requires direct physical measurement methods. Consult a healthcare professional for accurate body composition assessment.
How to add a percentage to a number?
To add a percentage to a number, multiply the number by (1 + percentage/100). For example, to add 15% to 200: 200 × (1 + 0.15) = 200 × 1.15 = 230. Use our Percentage Increase mode by entering the original number as the original value and the result as the new value.
How to subtract a percentage from a number?
To subtract a percentage from a number, multiply the number by (1 - percentage/100). For example, to subtract 20% from 100: 100 × (1 - 0.20) = 100 × 0.80 = 80. Use our Percentage Decrease mode to see this calculation step by step.
Am I pregnant calculator percentage?
A percentage calculator cannot determine pregnancy. Pregnancy is confirmed through medical tests such as home pregnancy tests or blood tests administered by healthcare professionals. If you think you might be pregnant, take a home pregnancy test or consult your doctor for accurate results and guidance.
What is the difference between percentage change and percentage difference?
Percentage change measures the change from an original value to a new value (used for increases and decreases over time). Percentage difference measures the relative difference between two values without designating one as the original. Use percentage change for before/after scenarios and percentage difference for comparing two equal values.
Is this percentage calculator free?
Yes, this percentage calculator is completely free to use with no usage limits, no sign-up required, and no hidden fees. All calculations are performed locally in your browser.
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Reviewed by FreeDeskTools Editorial Team
Percentage Calculator has been reviewed for accuracy, usability, privacy, and browser-side performance. FreeDeskTools tools are designed to run locally whenever possible, helping users complete tasks quickly without unnecessary data collection.
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