Calculate percentage (%) difference by entering two values below. You’ll see how much something increased or decreased, and you can also work backward to find the original.
Standard Calculation
⏷ Want to Work Backwards? Try our Reverse Calculator
This tool is completely free to use. We don’t collect personal information, and you don’t need to sign up or log in to make calculations.
How to Use the Percentage Difference Calculator
This tool helps you calculate how much one value has increased or decreased compared to another. It also includes a reverse mode to help you find the original number from a known percentage change.
Below, you’ll find examples, formulas, and helpful tips.
Quick Start
- To calculate change: Enter the original and new values and then click Calculate
- To work backwards: Enter the new value and percentage change and then click Calculate Original
Standard Percentage Change Formula
((New Value - Original Value) ÷ Original Value) × 100
Example 1: Price Increase
You bought something for $100. It now costs $143.
Result: 43% increase
Example 2: Price Decrease
Your website traffic dropped from 5,000 to 3,500.
Result: 30% decrease
Example 3: No Change
You compare 2,000 to 2,000.
Result: 0% change
Reverse Calculator Formula
Original Value = New Value ÷ (1 + (Percentage ÷ 100))
Use a negative percentage for decreases, positive for increases.
Example 1: 30% Increase
The final amount is $10,000 after a 30% increase.
Result: Original value ≈ $7,692.31
Example 2: 20% Decrease
You paid $800 after a 20% discount.
Result: Original value = $1,000