Reverse Percentage Calculator
Find the original number when you know a percentage and the result. Perfect for working backwards from discounts, taxes, and percentage-based calculations.
The value that represents the percentage
What is Reverse Percentage?
Reverse percentage calculation finds the original number when you know what percentage it represents and the result. It's the opposite of calculating a percentage - instead of finding what X% of Y is, you find what number Y is X% of.
This is useful when you know the discounted price and want to find the original price, or when you know a portion and need to find the whole.
How to Use the Reverse Percentage Calculator
- Enter percentage: Input the percentage value (e.g., 20 for 20%).
- Enter result value: Input the value that represents that percentage (e.g., if 80 is 20% of something, enter 80).
- Calculate: Click "Find Original Value" to see the original number.
Common Use Cases
Finding Original Price After Discount
If an item costs £80 after a 20% discount, the original price is £100. Use this calculator to find the original price.
Working Backwards from Tax
If you know the tax amount and rate, find the pre-tax amount. Example: £20 tax at 20% means the original amount was £100.
Finding Total from a Portion
If you know that 150 represents 30% of a total, find the total amount. The total would be 500.
Salary Calculations
If you know your take-home pay and what percentage of your salary it represents, find your gross salary.
Frequently Asked Questions
How is reverse percentage calculated?
Original Value = Result Value / (Percentage / 100). For example, if 80 is 20% of something: 80 / (20/100) = 80 / 0.20 = 400.
What if I know the discounted price?
If you know the price after discount, use the discount percentage. For example, if an item is £80 after a 20% discount, enter 20% and 80 to find the original £100 price.
Can I use this for increases?
Yes, if you know a value after an increase and the increase percentage, you can find the original value. For example, if £120 is 120% of the original (20% increase), the original is £100.
What if the percentage is over 100%?
The calculator works with percentages over 100%. For example, if 150 is 150% of something, the original value is 100.
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<p>Calculator: <a href="https://onlinecalculator.co.uk/percentage/reverse-percentage-calculator" target="_blank">Reverse Percentage Calculator</a> - OnlineCalculator.co.uk</p>APA Style Citation:
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