Percentage Change Calculator
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Percentage Change Calculator
A Percentage Change Calculator is a free online tool that helps you calculate the percentage increase or decrease between an original value and a new value. Instead of manually applying the percentage change formula, you can enter two values and get the result instantly.
Calculator Pool’s free percentage change calculator online also shows the absolute change and tells you whether the value increased, decreased, or remained unchanged.
Whether you are comparing prices, salaries, sales, marks, website traffic, investments, expenses, or other numerical values, a percentage change calculator can make comparisons quick and easy.
Important: Percentage change is a mathematical comparison between two values. The result should always be interpreted according to the context of the numbers being compared.
What Is Percentage Change?
Percentage change measures how much a value has changed relative to its original value.
It can show either an:
Increase
or
Decrease
For example, if a product price changes from:
₹100 → ₹120
the value increased by:
20%
If the price changes from:
₹100 → ₹80
the value decreased by:
20%
Percentage Change Formula
The standard formula for percentage change is:
Percentage Change = ((New Value − Original Value) ÷ |Original Value|) × 100
Where:
- Original Value is the starting value
- New Value is the ending value
- The absolute value of the original value is used as the denominator in the calculator’s comparison
Example: Increase
Original value:
100
New value:
120
Calculation:
((120 − 100) ÷ 100) × 100
= 20%
So the result is:
20% Increase
Example: Decrease
Original value:
100
New value:
80
Calculation:
((80 − 100) ÷ 100) × 100
= −20%
The magnitude is:
20% Decrease
How to Use the Percentage Change Calculator
Using Calculator Pool’s online percentage change calculator is simple.
Step 1: Enter the Original Value
Enter the starting value.
For example:
100
Step 2: Enter the New Value
Enter the value you want to compare against the original.
For example:
120
Step 3: Calculate
Click Calculate Change.
The calculator will show:
- Percentage change
- Absolute change
- Original value
- New value
- Increase or decrease
For the example above:
20% Increase
What Is Original Value?
The original value is the starting point of a comparison.
For example:
A product originally costs:
₹500
and later costs:
₹600
Then:
₹500 = Original Value
₹600 = New Value
The original value is important because percentage change is measured relative to it.
What Is New Value?
The new value is the value you are comparing with the original value.
For example:
Original Value = 500
New Value = 600
The difference is:
100
The percentage change tells you how large that difference is relative to the original value.
What Is Absolute Change?
The absolute change is the numerical difference between the original and new values.
Formula:
Absolute Change = New Value − Original Value
For example:
120 − 100 = 20
Therefore:
Absolute Change = 20
The percentage change then tells you how significant that difference is relative to the original value.
Percentage Increase Example
Suppose your monthly salary changes from:
₹40,000
to:
₹50,000
Absolute increase:
₹50,000 − ₹40,000 = ₹10,000
Percentage increase:
₹10,000 ÷ ₹40,000 × 100
= 25%
Therefore, the salary increased by:
25%
A percentage increase calculator can perform this calculation instantly.
Percentage Decrease Example
Suppose a product price changes from:
₹2,000
to:
₹1,500
Absolute decrease:
₹1,500 − ₹2,000 = −₹500
Percentage decrease:
₹500 ÷ ₹2,000 × 100
= 25%
Therefore:
25% Decrease
Percentage Change Example Table
| Original Value | New Value | Absolute Change | Percentage Change |
|---|---|---|---|
| 100 | 120 | 20 | 20% Increase |
| 100 | 150 | 50 | 50% Increase |
| 100 | 80 | 20 | 20% Decrease |
| 200 | 150 | 50 | 25% Decrease |
| 500 | 600 | 100 | 20% Increase |
| 1,000 | 900 | 100 | 10% Decrease |
Percentage Change vs Percentage Difference
These terms are often confused.
Percentage Change
Percentage change compares a new value with an original value.
Formula:
((New − Original) ÷ |Original|) × 100
The two values have a clear starting point and ending point.
Percentage Difference
Percentage difference is commonly used when comparing two values without treating one as the original or baseline.
A common formula is:
|A − B| ÷ ((A + B) ÷ 2) × 100
Therefore, percentage change and percentage difference are not always interchangeable.
Percentage Change vs Percentage Increase
A percentage increase is specifically a positive change.
For example:
100 → 125
= 25% Increase
Percentage change is broader and can represent either:
Increase
or
Decrease
That’s why a percentage change calculator is useful when the direction of change is not known in advance.
Percentage Change vs Percentage Decrease
A percentage decrease is a negative movement from an original value.
For example:
200 → 150
The decrease is:
50
Percentage decrease:
50 ÷ 200 × 100
= 25%
Therefore:
25% Decrease
Why Use a Percentage Change Calculator?
Calculating percentage change manually is straightforward for small numbers, but an online tool is useful when you need to perform many calculations quickly.
A percentage change calculator online can help you:
- Calculate increases
- Calculate decreases
- Compare two values
- Find absolute change
- Avoid manual arithmetic
- Check calculations
- Compare prices
- Compare salaries
- Analyze numerical data
Calculator Pool’s tool also automatically identifies whether the result represents an increase, decrease, or no change.
Percentage Change Calculator for Prices
A price change calculator can help you determine how much the price of a product has changed.
Example
Original price:
₹800
New price:
₹1,000
Difference:
₹200
Percentage change:
₹200 ÷ ₹800 × 100
= 25%
Therefore:
25% Increase
This can be useful when comparing old and new prices.
Percentage Change Calculator for Salary
A salary percentage increase calculator can help employees understand how much their salary has changed.
Suppose:
Old salary:
₹50,000
New salary:
₹55,000
Increase:
₹5,000
Percentage increase:
₹5,000 ÷ ₹50,000 × 100
= 10%
Therefore, the salary increased by:
10%
Percentage Change Calculator for Sales
Businesses can use a percentage change calculator to compare sales between two periods.
Suppose monthly sales increase from:
₹2,00,000
to:
₹2,50,000
Increase:
₹50,000
Percentage increase:
₹50,000 ÷ ₹2,00,000 × 100
= 25%
Therefore:
Sales increased by 25%.
Percentage Change Calculator for Revenue
Suppose annual revenue changes from:
₹10 lakh
to:
₹12 lakh
Absolute change:
₹2 lakh
Percentage change:
₹2 lakh ÷ ₹10 lakh × 100
= 20%
Therefore:
20% Increase
Percentage Change Calculator for Expenses
Percentage change can also be used to compare expenses.
Suppose monthly expenses increase from:
₹30,000
to:
₹36,000
Increase:
₹6,000
Percentage increase:
₹6,000 ÷ ₹30,000 × 100
= 20%
So expenses increased by:
20%
Percentage Change Calculator for Marks
Students can compare marks between two exams.
Suppose marks increase from:
60
to:
72
Difference:
12
Percentage increase:
12 ÷ 60 × 100
= 20%
Therefore:
20% Increase
This can be useful for tracking changes in test or exam performance.
Percentage Change Calculator for Website Traffic
Website owners can use percentage change to compare traffic between two periods.
Suppose website visits increase from:
10,000
to:
12,500
Increase:
2,500
Percentage increase:
2,500 ÷ 10,000 × 100
= 25%
So traffic increased by:
25%
Percentage Change Calculator for Investment Values
Percentage change can help compare the movement of an investment value.
Suppose a hypothetical investment changes from:
₹1,00,000
to:
₹1,10,000
Increase:
₹10,000
Percentage change:
10%
However, actual investment performance may involve dividends, fees, contributions, withdrawals, taxes, or other factors, so a simple two-value comparison may not represent the complete investment return.
Percentage Change Calculator for Weight
You can also calculate percentage change in weight.
Suppose:
Original Weight = 80 kg
New Weight = 72 kg
Change:
8 kg decrease
Percentage decrease:
8 ÷ 80 × 100
= 10%
Therefore:
10% Decrease
For health-related decisions, the calculation itself is mathematical and should not be treated as medical advice.
Percentage Change With Decimal Values
The calculator can also work with decimal values.
For example:
Original = 25.5
New = 30.6
Difference:
5.1
Percentage change:
5.1 ÷ 25.5 × 100
= 20%
Decimal values can therefore be used just like whole numbers.
Percentage Change With Negative Values
Negative values require additional care because the interpretation depends on the context.
For example:
Original = −100
New = −80
The numerical difference is:
20
but the meaning of the change can depend on what the numbers represent.
For this reason, negative-value percentage change should always be interpreted in context rather than automatically assuming that the direction has a real-world meaning.
Calculator Pool’s formula uses the absolute value of the original value as the denominator.
What Happens When the Original Value Is Zero?
Percentage change cannot be calculated using the standard formula when the original value is zero because it requires division by the original value.
For example:
Original = 0
New = 100
The expression would require:
100 ÷ 0
which is undefined.
Calculator Pool therefore requires the original value to be non-zero.
Percentage Change From 100 to 120
This is one of the simplest examples.
Original:
100
New:
120
Difference:
20
Percentage change:
20 ÷ 100 × 100
= 20%
Result:
20% Increase
Percentage Change From 100 to 80
Original:
100
New:
80
Difference:
−20
Percentage change magnitude:
20 ÷ 100 × 100
= 20%
Result:
20% Decrease
Percentage Change From 50 to 75
Original:
50
New:
75
Difference:
25
Percentage change:
25 ÷ 50 × 100
= 50%
Result:
50% Increase
Percentage Change From 200 to 150
Original:
200
New:
150
Difference:
−50
Percentage change:
50 ÷ 200 × 100
= 25%
Result:
25% Decrease
Percentage Change From 500 to 600
Original:
500
New:
600
Difference:
100
Percentage change:
100 ÷ 500 × 100
= 20%
Result:
20% Increase
Percentage Increase Calculator
A percentage increase calculator focuses specifically on positive changes.
The basic formula is:
Percentage Increase = ((New − Original) ÷ Original) × 100
when the new value is greater than the original.
For example:
100 → 140
Percentage increase:
40%
Calculator Pool’s Percentage Change Calculator can also handle this situation and identify the result as an increase.
Percentage Decrease Calculator
A percentage decrease calculator focuses on reductions.
Formula:
Percentage Decrease = ((Original − New) ÷ Original) × 100
when the new value is lower than the original.
For example:
200 → 150
Percentage decrease:
25%
Percentage Change and Discounts
A discount is generally expressed as a percentage reduction from an original price.
For example:
Original price:
₹1,000
Discount:
20%
Discount amount:
₹200
Final price:
₹800
For dedicated discount calculations, Calculator Pool’s Discount Calculator is more appropriate.
The Percentage Change Calculator is useful when you already have the original and final values and want to determine the percentage movement between them.
Percentage Change and Percentage Calculator
The Percentage Calculator and Percentage Change Calculator serve different purposes.
Percentage Calculator
Useful for questions such as:
What is 20% of ₹500?
Percentage Change Calculator
Useful for questions such as:
A value changed from 500 to 600. What was the percentage change?
Keeping these two tools separate helps users choose the correct calculator for their specific problem.
Percentage Change in Business and Finance
Percentage change is frequently used to compare:
- Revenue
- Expenses
- Sales
- Prices
- Salaries
- Profit
- Customer numbers
- Website traffic
- Financial figures
For example, if monthly revenue increases from ₹5 lakh to ₹6 lakh, the percentage increase is:
₹1 lakh ÷ ₹5 lakh × 100 = 20%
The calculation shows the relative size of the change rather than just the absolute difference.
Common Percentage Change Mistakes
Using the New Value as the Denominator
Percentage change normally uses the original value as the baseline.
Forgetting the Direction
A value can increase or decrease.
The calculator identifies the direction automatically.
Confusing Percentage Change With Percentage Points
A change in a percentage value is not always the same as a percentage change.
For example:
20% → 25%
is an increase of:
5 percentage points
but the percentage change relative to 20% is:
25%
These are different concepts.
Using Zero as the Original Value
The standard percentage change formula cannot divide by zero.
Percentage Points vs Percentage Change
This distinction is particularly important when comparing percentages.
Suppose a conversion rate changes:
20% → 25%
The change is:
5 percentage points
But percentage change is:
(25 − 20) ÷ 20 × 100
= 25%
So:
5 percentage points ≠ 5% change
The correct expression depends on what you are trying to measure.
Why the Original Value Matters
The same absolute change can produce different percentage changes depending on the starting value.
For example:
100 → 120
Change:
20
Percentage change:
20%
But:
200 → 220
Change:
20
Percentage change:
10%
The absolute change is identical, but the percentage change is different because the original values differ.
Frequently Asked Questions
What is a Percentage Change Calculator?
A Percentage Change Calculator calculates the percentage increase or decrease between an original value and a new value.
What is the percentage change formula?
The formula is:
((New Value − Original Value) ÷ |Original Value|) × 100
How do I calculate percentage increase?
Subtract the original value from the new value, divide by the original value, and multiply by 100.
How do I calculate percentage decrease?
Subtract the new value from the original value, divide by the original value, and multiply by 100.
What is the percentage change from 100 to 120?
The percentage change is 20% increase.
What is the percentage change from 100 to 80?
The percentage change is 20% decrease.
What is absolute change?
Absolute change is the numerical difference between the new value and original value.
New − Original
Can the original value be zero?
No. The standard percentage change formula requires a non-zero original value.
Is percentage change the same as percentage difference?
No. Percentage change uses a defined original value as the baseline, while percentage difference commonly uses the average of two values as the reference.
What is the difference between percentage points and percentage change?
Percentage points measure the direct difference between two percentages. Percentage change measures the relative change from the original percentage.
Can I use decimal values?
Yes. Percentage change can be calculated using decimal values.
Can I use negative values?
Yes, but the meaning of the result depends heavily on what the negative values represent.
Can I calculate salary percentage increase?
Yes. Enter the old salary as the original value and the new salary as the new value.
Can I calculate price percentage change?
Yes. Enter the old price and new price to determine the percentage movement.
Is the Percentage Change Calculator free?
Yes. Calculator Pool’s Percentage Change Calculator is free to use online.
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Percentage Change Calculator – Quick Summary
A Percentage Change Calculator helps you compare an original value with a new value and determine how much the value has changed in percentage terms.
The formula is:
Percentage Change = ((New Value − Original Value) ÷ |Original Value|) × 100
For example:
Original Value = 100
New Value = 120
The absolute change is:
20
The percentage change is:
20% Increase
For a decrease:
Original Value = 100
New Value = 80
The result is:
20% Decrease
Calculator Pool’s free percentage change calculator online also shows the absolute change and identifies the direction of the change.
Use the calculator to compare prices, salaries, sales, expenses, marks, website traffic, and other numerical values quickly.