How to Calculate Reverse Percentage
Reverse percentage calculations help you discover the original value before a discount (percentage decrease) or tax/markup (percentage increase) was added. Instead of starting from a base number and calculating where it ends up, you work backward from the final number to recover the starting reference point — a common need when a receipt, invoice, or price tag only shows you the after-the-fact total.
When Would I Use a Reverse Percentage?
- Post-tax base pricing: Calculating original item costs before sales tax additions.
- Original retail value: Calculating primary costs of discount markdown objects.
- Baseline metrics: Discovering original monthly data targets before specific percentage gains.
Example 1: Reversing a Price Markup
An item is sold for $120 after a 20% markup:
- Decimal equivalent of 20% change: 1 + (20/100) = 1.2
- Divide final price by decimal factor: 120 / 1.2 = $100.
- The original price before the markup was $100.
Example 2: Finding the Pre-Discount Price
A jacket is on sale for $68 after a 15% discount. What was the original price?
- Decimal equivalent of a 15% decrease: 1 - (15/100) = 0.85
- Divide the sale price by the decimal factor: 68 / 0.85 = $80.
- The jacket's original price before the discount was $80.
Reverse Percentage FAQ
Q: How do I calculate reverse percentage in Excel?
If the final value represents an increase, use the formula =FinalValue/(1+Percentage). If it is a decrease, use =FinalValue/(1-Percentage).
Q: What does reverse percentage mean?
It is the mathematical process of finding the original starting number before a percentage addition or subtraction was applied.
Q: What is $120 after a 20% increase reversed?
Divide $120 by 1.20, which results in the original baseline value of $100.
Q: How is reverse percentage different from a regular percentage increase or decrease calculation?
A regular percentage increase or decrease starts from the original value and calculates the new value. Reverse percentage works in the opposite direction: it starts from the final value and calculates back to the original, which is why you divide (rather than multiply) by the percentage factor.