Percentage Calculator
What is X% of Y?
X percent of Y
Percentage Difference between two values
Find part from percent and total
Percent change from original to new value
What percent is part of total?
Find X value of percent
Value after increasing by percent
Value after decreasing by percent
X is what percent of Y?
Convert fraction to percent
Convert decimal to percent
Convert percent to decimal
Final value after percent change
Original value before percent increase
Original value before percent decrease
What percent one number is of another
Reverse percent increase to find original
Reverse percent decrease to find original
Percentage of a percentage
Related Calculators
Online Percentage Calculator – Quick and Accurate Results
Percentages affect almost every part of daily life — from calculating discounts while shopping, working out grade percentages, to analyzing financial reports. Our freeOnline Percentage Calculator makes these calculations easy, fast, and 100% accurate. Designed for both students and professionals, this all-in-one tool solves every percentage-related problem instantly.
Instead of using multiple tools, this calculator brings everything together. Whether you’re finding what X% of Y is, checking percentage increase or decrease, or comparing two values in percentage terms — everything is handled in real time. With over 20 built-in functions, clear examples, and step-by-step formulas, you’ll never have to guess the math again.
Percentages matter everywhere — in classrooms, businesses, savings plans, data analysis, sports performance reviews, and even everyday shopping. This calculator isn’t just a number cruncher; it’s an easy-to-use learning aid that explains the logic behind each calculation. Best of all, it works instantly on any device, no downloads or sign-ups required.
For quick, flexible, and reliable results, bookmark this page and make it your go-to percentage calculator for school, work, or personal use.
Most Popular Percentage Calculations
1. What is X% of Y?
The simplest and most common calculation: finding the value that represents X percent of another number Y. Perfect for discounts, fees, commissions, or grades.
Result = (X / 100) × Y
Example: 20% of 150 = 30
2. X is What Percent of Y?
Find out what percentage one number is of another.
Percentage = (X / Y) × 100
Example: 30 is what percent of 200? → 15%
3. Percentage Increase
Works out how much a value has increased compared to its original.
% Increase = (New - Old) / Old × 100
Example: Old = 100, New = 120 → 20% increase
4. Percentage Decrease
Use this when a value drops from its original.
% Decrease = (Old - New) / Old × 100
Example: Old = 200, New = 150 → 25% decrease
5. Percentage Difference
Compares how much two numbers differ in percentage terms.
Difference % = |X - Y| / ((X + Y) / 2) × 100
Example: Between 80 and 100 = 22.22%
6. Fraction to Percent
Quickly convert any fraction into percent form.
Percent = (Numerator ÷ Denominator) × 100
Example: 3/4 → 75%
7. Decimal to Percent
Turn decimals into percentages instantly.
Percent = Decimal × 100
Example: 0.85 = 85%
8. Percent to Decimal
Decimal = Percent ÷ 100
Example: 65% = 0.65
9. Reverse % Increase / Decrease
Find the original value before a given increase or decrease was applied.
Original = New Value ÷ (1 ± Percent/100)
Example: Final = 120 after 20% increase → Original = 100
10. Percent Comparison
Compare two sets of numbers in percentage terms.
Example: 60 compared to 80 → 75%
11. Percent of a Ratio
Turn ratios into percentages.
Percent = (Numerator ÷ Denominator) × 100
Example: 4:5 = 80%
12. Percent of a Percent
Find the compound effect when one percent is applied to another.
Example: 50% of 20% = 10%
FAQs – Percentage Calculator
1. How do you calculate percentage of marks?
Divide marks obtained by total marks, then multiply by 100.
2. How do you calculate percentage increase?
(New - Old) ÷ Old × 100 = Percentage Increase
3. How to calculate discount percentage?
(Original Price - Sale Price) ÷ Original Price × 100 = Discount %
4. Can I calculate percentage in Excel?
Yes. Use =(Part/Total)*100 or set the cell format to percentage.
5. How to convert fractions or decimals into percentages?
Fraction ÷ Denominator × 100 = Percent; Decimal × 100 = Percent
6. How to reverse a percentage calculation?
Use reverse formulas to find the original number before percentage adjustments.
7. What does "X% of Y" mean?
It means “how much is X percent of Y.” Example: 20% of 150 is 30.
8. Is this tool free?
Yes. It’s completely free and works instantly online on any device.
Conclusion
The Percentage Calculator is more than just a math tool. It’s designed to save time, reduce errors, and help you better understand how percentages impact everyday life — from money to studies, discount deals to business reports. With 20+ built-in functions, real-world examples, and a user-friendly interface, it’s the only percentage calculator you need.
Whether you’re a student calculating marks, a business professional reviewing data, or simply figuring out a shop discount, this tool has you covered. No setup, no logins, always available on desktop or mobile.
Bookmark this page and make GuideCalculator’sPercentage Calculator your trusted companion for quick, accurate, and stress-free calculations.