Reverse Percentage Calculator
This calculator helps you find the original value before a known percentage increase or decrease was applied. Whether you're working with discounted prices, tax-inclusive amounts, or past financial values, it quickly calculates what the number was before the percentage change.
Find the Original Value from Final and Percentage
Reverse Percentage Formula
Explanation:
To reverse a percentage change, divide the final value by either $$1 + %/100$$ (for increase) or $$1 – %/100$$ (for decrease). This reveals the original amount before the change.
Reverse Percentage – Calculation Example
Final price after 20% discount = $80
Step 1: 1 – (20 / 100) = 0.8
Step 2: 80 / 0.8 = 100
Result: Original price was $100
Final value after 15% increase = 115
Step 1: 1 + (15 / 100) = 1.15
Step 2: 115 / 1.15 = 100
Result: Original value was 100
Reverse percentage is frequently used in business, finance, retail, and everyday life when you know the result after a percentage change and want to calculate the original number. It’s especially useful for undoing discounts, taxes, markups, and losses to uncover the base value.