Percentage Change In Price Calculator
This calculator determines the percentage change from an original price to a new price. It can be used for stock prices, sales discounts, salary changes, and more.
Enter the Original Price (the starting value) and the New Price (the ending value). The calculator will show the percentage increase or decrease.
Enter Prices to Calculate Change
Understanding Percentage Change & The Formula
What is Percentage Change?
Percentage change is a simple mathematical concept that represents the degree of change over time. It is used to express the difference between a past value (original) and a present value (new) as a percentage of the original value. A positive result indicates a percentage increase, while a negative result indicates a percentage decrease.
The Percentage Change Formula
The standard formula to calculate the percentage change is:
Percentage Change = [ (New Price - Original Price) / Original Price ] * 100
This formula is the core of this calculator and is widely used in finance, statistics, and everyday life to quantify changes.
Example Calculation
EX: A product's price increased from $200 to $250. Calculate the percentage change.
1. Subtract the original price from the new price: $250 - $200 = $50.
2. Divide the difference by the original price: $50 / $200 = 0.25.
3. Multiply by 100 to get the percentage: 0.25 * 100 = 25%.
Result: The price had an increase of 25%.
10 Real-Life Percentage Change Examples
Click on an example to see the step-by-step calculation.
Example 1: Retail Sale Discount
Scenario: A jacket was originally priced at $120 and is now on sale for $90.
1. Values: Original Price = 120, New Price = 90.
2. Formula: Pct Change = [(90 - 120) / 120] * 100
3. Calculation: Pct Change = [-30 / 120] * 100 = -0.25 * 100 = -25%
Result: A decrease of 25.00%.
Example 2: Stock Price Increase
Scenario: You bought a stock at $45.50 per share, and it is now worth $52.78.
1. Values: Original Price = 45.50, New Price = 52.78.
2. Formula: Pct Change = [(52.78 - 45.50) / 45.50] * 100
3. Calculation: Pct Change = [7.28 / 45.50] * 100 = 0.16 * 100 = 16%
Result: An increase of 16.00%.
Example 3: Website Traffic Growth
Scenario: A website had 15,000 visitors last month and 18,500 visitors this month.
1. Values: Original Value = 15000, New Value = 18500.
2. Formula: Pct Change = [(18500 - 15000) / 15000] * 100
3. Calculation: Pct Change = [3500 / 15000] * 100 ≈ 0.2333 * 100 ≈ 23.33%
Result: An increase of 23.33%.
Example 4: Real Estate Value Decrease
Scenario: A house was valued at $450,000 last year but is now valued at $435,000.
1. Values: Original Price = 450000, New Price = 435000.
2. Formula: Pct Change = [(435000 - 450000) / 450000] * 100
3. Calculation: Pct Change = [-15000 / 450000] * 100 ≈ -0.0333 * 100 ≈ -3.33%
Result: A decrease of 3.33%.
Example 5: Salary Raise
Scenario: An employee's annual salary is raised from $60,000 to $63,000.
1. Values: Original Price = 60000, New Price = 63000.
2. Formula: Pct Change = [(63000 - 60000) / 60000] * 100
3. Calculation: Pct Change = [3000 / 60000] * 100 = 0.05 * 100 = 5%
Result: An increase of 5.00%.
Example 6: Utility Bill Change
Scenario: The electricity bill was $85 in July and $72.25 in August.
1. Values: Original Price = 85, New Price = 72.25.
2. Formula: Pct Change = [(72.25 - 85) / 85] * 100
3. Calculation: Pct Change = [-12.75 / 85] * 100 = -0.15 * 100 = -15%
Result: A decrease of 15.00%.
Example 7: "Shrinkflation" (Product Size Change)
Scenario: A bag of chips used to be 200g but is now 175g for the same price. Calculate the percentage change in size.
1. Values: Original Value = 200, New Value = 175.
2. Formula: Pct Change = [(175 - 200) / 200] * 100
3. Calculation: Pct Change = [-25 / 200] * 100 = -0.125 * 100 = -12.5%
Result: A decrease of 12.50% in product size.
Example 8: Restaurant Bill Tip Calculation
Scenario: A meal costs $50. You add a $10 tip. What is the percentage change from the original bill to the total?
1. Values: Original Price = 50, New Price = 60 (50 + 10).
2. Formula: Pct Change = [(60 - 50) / 50] * 100
3. Calculation: Pct Change = [10 / 50] * 100 = 0.2 * 100 = 20%
Result: An increase of 20.00% (a 20% tip).
Example 9: Fuel Price Drop
Scenario: The price of gas was $3.89 per gallon and dropped to $3.59.
1. Values: Original Price = 3.89, New Price = 3.59.
2. Formula: Pct Change = [(3.59 - 3.89) / 3.89] * 100
3. Calculation: Pct Change = [-0.30 / 3.89] * 100 ≈ -0.0771 * 100 ≈ -7.71%
Result: A decrease of 7.71%.
Example 10: No Price Change
Scenario: A subscription service costs $9.99 per month, and the price remains $9.99 next month.
1. Values: Original Price = 9.99, New Price = 9.99.
2. Formula: Pct Change = [(9.99 - 9.99) / 9.99] * 100
3. Calculation: Pct Change = [0 / 9.99] * 100 = 0 * 100 = 0%
Result: No Change (0.00%).
Frequently Asked Questions (FAQs)
1. How do I use this calculator?
Enter the starting number in the "Original Price" field and the final number in the "New Price" field. Click "Calculate Percentage Change" to see the result.
2. What does a positive or negative result mean?
A positive result (e.g., 15%) means there was an increase of that percentage. A negative result (e.g., -10%) means there was a decrease. The calculator clarifies this with the words "Increase" or "Decrease".
3. Why can't the "Original Price" be zero?
The formula requires dividing by the original price. In mathematics, division by zero is an undefined operation, so it's not possible to calculate a percentage change from zero.
4. Can I use numbers with decimal points?
Yes. The calculator is designed to handle both whole numbers (integers) and numbers with decimal places (e.g., 199.99).
5. What is the formula used for the calculation?
The calculator uses the standard formula: Percentage Change = [ (New Price - Original Price) / Original Price ] * 100.
6. How do I calculate the new price if I know the percentage change?
To find the new price after an increase, use: New Price = Original Price * (1 + (Percentage / 100)). For a decrease, use: New Price = Original Price * (1 - (Percentage / 100)).
7. What if the new and original prices are the same?
If both values are identical, the calculator will correctly show a 0.00% change, as there has been no increase or decrease.
8. Why does the "Decrease" result not show a minus sign?
For clarity. A result of "-20%" is displayed as a "Decrease of 20.00%". The word "Decrease" and the red color already indicate the negative direction of the change, making the minus sign redundant.
9. Is my data saved or stored anywhere?
No. This calculator operates entirely within your browser (it's a "client-side" tool). None of the information you enter is sent to or stored by any server.
10. What is the difference between percentage change and percentage point change?
Percentage change is relative to the original value (e.g., a change from 10% to 15% is a 50% increase). A percentage point change is the simple numerical difference (a change from 10% to 15% is a 5 percentage point increase). This tool calculates percentage change.
