Percentage Change Calculator

What This Calculator Does

The Percentage Change Calculator measures the percentage increase or decrease between an old value and a new value. This calculator is essential for tracking growth, measuring performance changes, analyzing trends, and comparing values over time.

Formula:

Percentage Change = (New − Old)Old × 100

How to interpret the result: A positive percentage indicates an increase (growth, gain). A negative percentage indicates a decrease (decline, loss).

For a comprehensive explanation of this formula and when to use it, read our guide How to Calculate Percentage Increase and Decrease.

How the Formula Works

The percentage change formula measures how much a value changed relative to its starting point. Breaking it down into steps makes it easy to understand and apply:

Step 1: Find the difference (New - Old)
Subtract the old value from the new value to get the absolute change.

Step 2: Divide by the old value
This creates a ratio showing how large the change is relative to the starting point.

Step 3: Multiply by 100 to convert to percentage
This expresses the ratio as a percentage for easier interpretation.

Example 1: Positive Change (Increase)

Old value: 200, New value: 250

• Difference: 250 − 200 = 50
• Divide by old value: 50 ÷ 200 = 0.25
• Multiply by 100: 0.25 × 100 = 25%
• Result: +25% (25% increase)

Example 2: Negative Change (Decrease)

Old value: 300, New value: 240

• Difference: 240 − 300 = -60
• Divide by old value: -60 ÷ 300 = -0.20
• Multiply by 100: -0.20 × 100 = -20%
• Result: -20% (20% decrease)

Real-World Use Cases

Percentage change calculations help you measure and communicate changes in business metrics, financial data, academic performance, and personal tracking. Here are practical examples:

Business: Revenue growth from quarter to quarter
Q1 revenue: $84,000, Q2 revenue: $102,000
Percentage change = ((102,000 − 84,000) / 84,000) × 100 = (18,000 / 84,000) × 100 = 21.43% increase

Finance: Stock price changes
Stock price yesterday: $50, Stock price today: $58
Percentage change = ((58 − 50) / 50) × 100 = (8 / 50) × 100 = 16% increase

Education: Test score improvement tracking
First test: 72 points, Second test: 85 points
Percentage change = ((85 − 72) / 72) × 100 = (13 / 72) × 100 = 18.06% increase

Personal: Weight loss/gain tracking
Starting weight: 180 lbs, Current weight: 165 lbs
Percentage change = ((165 − 180) / 180) × 100 = (-15 / 180) × 100 = -8.33% (8.33% decrease)

For real-world context on salary changes and how inflation affects purchasing power, see our article Salary Raise vs Inflation: Understanding Real Change.

Excel and Spreadsheet Formulas

The percentage change formula translates directly into Excel or Google Sheets, making it easy to track changes across rows of data.

Basic Excel formula:
=((New-Old)/Old)*100

Alternative (with percentage formatting applied to cell):
=(New-Old)/Old
Then format the cell as percentage (Excel will multiply by 100 automatically)

Example with specific values:
Old value = 200, New value = 250
=((250-200)/200)*100 → Result: 25

Using cell references for repeatable calculations:
If old value is in cell A1 and new value is in cell B1:
=((B1-A1)/A1)*100

This pattern works for any row, making it perfect for tracking changes across datasets. Copy the formula down to calculate percentage changes for multiple rows of data automatically.

When to Use Other Calculators

The Percentage Change Calculator measures changes that already happened, but AnyPercent offers other calculators for different percentage scenarios:

Increase/decrease calculator: Use this when you want to apply a percentage change to a base value rather than measure an existing change. For example, "Increase $100 by 15%" gives you the new value ($115), while percentage change measures the difference between two known values.

Percentage difference calculator: Use this when comparing two values without a time relationship or when you want a non-directional comparison that treats both values equally.

Compound percentage calculator: Use this for repeated percentage changes over multiple periods, such as calculating growth or decline compounded over years, quarters, or months.

Percent of number calculator: Use this to find what a percentage of a single value equals, without comparing two values.

Return to the home page to access all percentage calculators in one interface.

Reverse Percentage: Find the Original Value

This page also covers reverse percentage thinking: finding the original value when you know the final result and the percentage that was applied. Two formulas handle the two directions:

Reverse decrease (undo a discount or loss):

Original = Result ÷ (1 − Percent ÷ 100)

Reverse increase (undo a markup or raise):

Original = Result ÷ (1 + Percent ÷ 100)

Worked Example — Reverse Discount

An item is on sale for $45 after a 25% discount. What was the original price?

• Discount factor: 1 − 25 ÷ 100 = 0.75
• Original = 45 ÷ 0.75 = $60

Worked Example — Reverse Increase

A subscription now costs $108 after an 8% price increase. What was it before?

• Increase factor: 1 + 8 ÷ 100 = 1.08
• Original = 108 ÷ 1.08 = $100

This reverse workflow is part of the same change-logic family and is used frequently in pricing analysis. For discount-specific scenarios, use the discount calculator. Read more in our guides on discount formula and reverse discount and markup vs margin with practical percent examples.