How do I calculate percentage change?

Percentage change = ((New Value - Old Value) ÷ Old Value) × 100. Positive result = increase, negative = decrease. Example: Price went from ₹100 to ₹120 = ((120-100)/100) × 100 = +20% increase.

What's the difference between percentage change and percentage difference?

Percentage change compares new vs old with direction (increase/decrease). Percentage difference compares two values without direction, using average as base: |A-B| ÷ ((A+B)/2) × 100. Use change for time-based comparisons, difference for comparing two independent values.

How do I calculate percentage of a number?

Percentage of a number = (Percentage ÷ 100) × Number. Example: 15% of 500 = (15/100) × 500 = 75. To find what percentage A is of B: (A ÷ B) × 100.

Why doesn't +20% followed by -20% return to original?

The base changes! ₹100 + 20% = ₹120. ₹120 - 20% = ₹96 (not ₹100). The 20% decrease is on ₹120, not ₹100. To return to original after +20%, you need -16.67% decrease (20 ÷ 120 × 100).

Percentage Difference Calculator - Calculate % Change

Understanding Percentage Calculations

Percentage change is one of the most commonly used calculations in finance, business, and everyday life. Whether tracking investment returns, comparing prices, measuring growth, or analyzing data - understanding percentage calculations is essential.

Our calculator handles percentage change, percentage of numbers, and finding what percentage one number is of another.

Percentage Change Formula

Percentage Change = ((New Value - Original Value) ÷ Original Value) × 100

Positive result = Percentage increase
Negative result = Percentage decrease

Example Calculations

Scenario	Calculation	Result
₹1,000 → ₹1,200	((1200-1000)/1000) × 100	+20% increase
₹500 → ₹400	((400-500)/500) × 100	-20% decrease
85 kg → 80 kg	((80-85)/85) × 100	-5.9% decrease
₹50 → ₹75	((75-50)/50) × 100	+50% increase

Other Percentage Formulas

Percentage of a Number

X% of Y = (X ÷ 100) × Y

Example: 18% of ₹2,500 = (18/100) × 2500 = ₹450

What Percentage is X of Y?

Percentage = (X ÷ Y) × 100

Example: What % is 45 of 180? = (45/180) × 100 = 25%

Percentage Difference (Symmetric)

% Difference = |A - B| ÷ ((A + B) / 2) × 100

Used when comparing two values without a "before/after" relationship.

Common Applications

Field	Use Case	Example
Investment	Returns, CAGR	Portfolio up 15% YoY
Sales	Growth, targets	Sales grew 25% vs last quarter
Discounts	Price reductions	30% off sale price
Tax	GST, income tax	18% GST on services
Health	Weight change	Lost 8% body weight
Economics	Inflation, GDP	Inflation at 5.2%

The Percentage Change Trap

A common mistake: thinking +X% and -X% cancel out. They don't!

Starting value	₹100
After +50%	₹150
After -50% (on ₹150)	₹75 (not ₹100!)

To return to original after +50%, you need only -33.33% (50/150 × 100).
After -50%, you need +100% to return to original (50/50 × 100).

Reverse Percentage Calculations

Find Original Value Before Increase

Original = Final Value ÷ (1 + Percentage/100)

Example: Price after 20% increase is ₹600. Original = 600 ÷ 1.20 = ₹500

Find Original Value Before Decrease

Original = Final Value ÷ (1 - Percentage/100)

Example: Price after 25% discount is ₹750. Original = 750 ÷ 0.75 = ₹1,000

Percentage Points vs Percentage

These are different concepts:

Percentage points: Absolute difference between percentages
Percentage change: Relative change in the percentage value

Interest rate moves from 6% to 8%
Change in percentage points	2 percentage points (8 - 6)
Percentage change in rate	33.3% increase ((8-6)/6 × 100)

Quick Reference Table

Change	Multiply by	Divide by
+10%	1.10	0.909
+20%	1.20	0.833
+25%	1.25	0.80
+50%	1.50	0.667
+100%	2.00	0.50
-10%	0.90	1.111
-20%	0.80	1.25
-25%	0.75	1.333
-50%	0.50	2.00

Frequently Asked Questions

How do I calculate CAGR (Compound Annual Growth Rate)?

CAGR = (Ending Value / Beginning Value)^(1/Years) - 1 × 100. It shows average yearly growth rate over multiple years. ₹1,00,000 growing to ₹1,61,051 in 5 years = 10% CAGR. Use ourROI Calculator for CAGR calculations.

How do I calculate percentage increase needed to recover a loss?

Recovery % = (Loss% ÷ (100 - Loss%)) × 100. After 20% loss, you need 25% gain to break even (20÷80×100). After 50% loss, you need 100% gain. This is why limiting losses is crucial in investing!

What's the percentage markup vs margin?

Markup = (Profit/Cost) × 100. Margin = (Profit/Selling Price) × 100. A 50% markup on ₹100 cost = ₹150 selling price. The margin is 33.3% (₹50/₹150). Markup is always higher than margin for same profit.

How do I handle negative numbers in percentage change?

The formula works but interpretation needs care. Going from -₹50 to +₹50 isn't "200% increase" in the traditional sense. For losses/profits crossing zero, use absolute change (₹100) or describe as "moved from ₹50 loss to ₹50 profit."