Master Percentage Calculations in Seconds
Use the calculator above for instant results, then explore the formulas and real-world examples below to understand the math behind your calculations.
Use the calculator above for instant results, then explore the formulas and real-world examples below to understand the math behind your calculations.
Formula: (X ÷ 100) × Y
Example:
18% of $850 = $153
Perfect for discounts & tips
Formula: (A ÷ B) × 100
Example:
87 out of 120 = 72.5%
Great for grades & scores
Formula: ((New−Old) ÷ Old) × 100
Example:
$120 → $156 = +30% increase
Track growth & changes
💡 This tool is free, unlimited, and works on all devices. No account or registration required.
Calculate savings on "30% off" deals, compare prices across stores, and figure out final costs with sales tax. Example: A $200 jacket at 40% off costs $120.
Understand raises, bonuses, and job offers. A 6% raise on $50,000 means $3,000 more per year ($250/month)—essential for budget planning.
Convert test scores to percentages. Scoring 42 out of 60 equals 70%. Compare performance across different exams and track academic progress.
Track portfolio growth, understand interest rates, and make smarter financial decisions. A 12% gain on $10,000 = $1,200 profit.
Master these three core formulas and you'll be able to solve any percentage problem without hesitation:
This is your go-to formula for discounts, tips, taxes, and any time you need to find a portion of a whole value.
Formula: X% of Y = (X ÷ 100) × Y
Real-World Example: You're buying a laptop that costs $850, and the store offers an 18% discount. How much money will you save?
Answer: You save $153, paying only $697 for the laptop.
More Examples: 15% tip on a $60 meal = $9 | 7.5% sales tax on $200 = $15
Perfect for converting any fraction or score into a percentage. Essential for grades, completion rates, and performance metrics.
Formula: Percentage = (A ÷ B) × 100
Real-World Example: Your daughter scored 87 points out of a possible 120 points on her science exam. What's her percentage score?
Answer: She scored 72.5% on the exam.
More Examples: Completed 45 of 60 tasks = 75% done | Read 180 of 300 pages = 60% complete
Track changes over time—whether it's business growth, price fluctuations, population changes, or investment returns.
Formula: Percentage Change = ((New Value − Old Value) ÷ Old Value) × 100
Example (Increase): Your monthly electric bill was $120 in January and rose to $156 in February. What's the percentage increase?
Answer: Your electric bill increased by 30%.
Example (Decrease): A company reduced its workforce from 500 to 425 employees. What's the percentage decrease?
Answer: The workforce decreased by 15%.
More Examples: Stock went from $50 to $65 = +30% gain | Weight dropped from 180 to 162 lbs = −10%
💡 Pro Tip: Once you understand these three formulas, you can solve almost any percentage problem in daily life. Practice with real numbers from your own expenses, grades, or investments to build confidence!
Yes! 100% free with no hidden costs, subscriptions, or premium features. Perform unlimited calculations without creating an account or providing any personal information. CalculateGloba will always remain free to use.
Absolutely. The calculator uses standard mathematical formulas taught in schools and used by financial institutions worldwide. The tool has been tested extensively to ensure accuracy.
For critical financial or legal decisions involving significant money, we recommend verifying results with a certified professional. For everyday use (shopping, budgeting, grades), the tool is more than sufficient.
No. All calculations happen locally in your browser using JavaScript. Your numbers never leave your device or get sent to our servers. We don't ask for personal information, don't track your calculations, and don't create user profiles. It's as private as using a physical calculator.
Yes! The formulas and examples are based on standard mathematics and appropriate for homework, business reports, financial planning, and research. Students can reference these formulas in assignments, and professionals can incorporate them into spreadsheets and presentations.
Yes! Fully responsive and works seamlessly on smartphones, tablets, and computers. Whether you're using iPhone, Android, iPad, or any device, you'll get accurate results and an easy-to-use interface. Bookmark this page for quick access on the go.
First, double-check your numbers and calculation type. Many unexpected results come from input errors (like entering 1000 instead of 100) or selecting the wrong calculation type.
If your inputs are correct, review the formula explanations above. Sometimes results seem counterintuitive but are mathematically correct—for example, a 50% decrease followed by a 50% increase doesn't return you to the original number.
Yes! Our goal is to build a comprehensive suite of simple calculation tools covering ratios, unit conversions, financial calculations, and more. Each tool will provide quick results while explaining the underlying math. New tools will be added gradually based on quality and user needs.