Price Increase & Decrease Calculator

Easily calculate the percentage change between two prices or find the final cost after a discount or markup. Whether you are a shopper looking for a deal or a business owner setting margins, this tool provides instant accuracy.

Price Adjustment

— OR APPLY PERCENTAGE —

Use negative (e.g., -20) for discounts
Percentage Decrease
-15.00%
Difference Amount -$15.00
Price Multiplier 0.85x
Reverse Markup +17.65%

Verdict

Price Drop

How to Calculate Price Increases and Decreases

Understanding price fluctuations is key to managing a budget or a business. A price increase represents a markup, often due to inflation or higher demand, while a price decrease represents a discount or sale.

The Asymmetry of Percentages

One of the most important lessons in finance is that percentages are not symmetrical. If a price drops by 50%, it must increase by 100% just to return to its original value. This is why large losses are much harder to recover from than small ones.

Quick Calculation Formulas:

  • Find % Change: ((New Price - Old Price) / Old Price) × 100
  • Apply Increase: Old Price × (1 + Percentage / 100)
  • Apply Discount: Old Price × (1 - Percentage / 100)

Pricing & Percentages FAQ

1. What is the difference between markup and margin?
Markup is the percentage added to the cost price to determine the selling price. Margin is the percentage of the selling price that is profit. A 50% markup results in a 33.3% profit margin.
2. How do I calculate a 20% discount quickly?
The fastest way is to multiply the price by 0.8. Since 100% - 20% = 80%, multiplying by 0.8 gives you the final discounted price directly.
3. Why did a 10% increase followed by a 10% decrease not return to the original price?
This is because the 10% decrease is calculated on a larger number (the new, increased price). For example, $100 + 10% = $110. Then $110 - 10% = $99. You end up with 1% less than you started with.
4. How do I find the original price if I only know the discounted price?
Divide the discounted price by (1 - discount rate). If you paid $80 after a 20% discount, calculate: 80 / 0.8 = $100.
5. What is "Compound Price Increase"?
This occurs when prices increase multiple times in succession (like annual inflation). Each increase is applied to the already increased price from the previous period.
6. How is sales tax handled in price increases?
Sales tax is essentially a price increase mandated by the government. It is usually applied to the final subtotal after any discounts have been deducted.
7. What does a negative percentage change mean?
A negative percentage change simply indicates a decrease in value or a price drop. In this calculator, it will be highlighted as a "Price Drop."
8. Is "Percent Change" the same as "Percentage Points"?
No. If an interest rate moves from 5% to 6%, it is a 1 percentage point increase, but it is a 20% price increase in the cost of borrowing.