Percentage Calculator
Use this percentage calculator to find percentages, exam scores, and value changes. Choose a calculator below and get instant results.
Find X% of Y?
Use this calculator to find a percentage of a number.
- Enter the percentage (X).
- Enter the total value (Y).
- Click Calculate to see the result.
Example:
20% of 150 equals 30.
This percentage calculator is useful for discounts, tips, and finding part of a total.
Find X as a percent of Y?
Use this calculator to find what percent one number is of another.
- Enter the value (X).
- Enter the total (Y).
- Click Calculate to get the percentage.
Example:
45 out of 150 equals 30%.
This is commonly used for exam scores and grade calculations.
Percentage Increase
Use this calculator to measure how much a value has increased.
- Enter the old value.
- Enter the new value.
- Click Calculate to find the increase percentage.
Example:
From 200 to 250 equals a 25% increase.
This is useful for growth, raises, and profit changes.
Percentage Decrease
Use this calculator to measure how much a value has decreased.
Example:
- Enter the old value.
- Enter the new value.
- Click Calculate to find the decrease percentage.
From 200 to 150 equals a 25% decrease.
This is helpful for discounts, losses, and price drops.
About Owner
Henry Ethan is the owner of Grading Calculators Hub and a mathematics teacher with over 15 years of classroom experience. He has worked closely with students across different grade levels, helping them understand grading systems, scores, and academic performance. Every calculator and explanation on this site reflects real teaching experience and practical classroom needs.
How to Use the Percentage Calculator
This percentage calculator is simple to use.
- Choose the calculator you need
- Enter the numbers
- Click Calculate
- View the result instantly
The tool works on phones, tablets, and computers.
What Is a Percentage?
A percentage shows how much one number is compared to another out of 100.
- 50% means 50 out of 100
- 100% means the full value
- 150% means one and a half times
Percentages are used in exams, grades, discounts, and value changes.
Percentage Formulas Used
This calculator uses standard formulas taught in schools.
What is X% of Y?
(X ÷ 100) × Y
Example:
25% of 150 equals 37.50
X is what percent of Y?
(X ÷ Y) × 100
Example:
43 out of 160 equals 26.88%.
Percentage increase
((New − Old) ÷ Old) × 100
Example:
From 230 to 280 equals a 1.739130% increase.
Percentage decrease
((Old − New) ÷ Old) × 100
Example:
From 240 to 160 equals a 33.33% decrease.
A percentage shows how much one number is compared to another out of 100. It is commonly used in exams, discounts, marks, finance, and daily calculations.
Read Latest Articles
Helpful guides and calculators explained in simple words
Percentage Grading Example
To convert marks into a percentage:
Divide the score by total marks.
Multiply by 100.
Example:
A student scores 72 out of 90.
(72 ÷ 90) × 100 = 80%
For more than one subject, add all marks first.
Real-Life Percentage Examples
- A value changes from 50 to 60. This is a 20% increase
- 20% of 150 equals 30. Useful for discounts
- 75 out of 100 equals 75%. Common in exams
These examples show how percentages work in daily life.
When to Use Each Calculator
Find X% of Y
Use for discounts and parts of a total
Find X as a percent of Y
Use for grades and score comparison
Percentage increase
Use for growth and raises
Percentage decrease
Use for discounts and losses
Precision and Rounding
Results are shown up to two decimal places.
Some schools or systems use different rounding rules.
Always follow the method required for official work.
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