Reverse Percentage Calculator
🔢 Number, percentages & ratio. Use the Reverse percentage formula to find original value, value after the change, percentage change: pick the value you want, type the others, and the answer updates as you go.
Finds the price before a percentage was added or taken off.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Original value | no unit |
| Value after the change | no unit |
| Percentage change | % |
Worked example
Find the original value when Value after the change = 96, Percentage change = 20 %.
Using original = new/(1 + p/100): Original value = 80.
Frequently asked questions
What is the formula for Reverse percentage?
original = new/(1 + p/100). Finds the price before a percentage was added or taken off.
What do the letters stand for, and what units are used?
Original value, Value after the change, Percentage change in %.
How do you calculate original value?
Put the values into original = new/(1 + p/100). For example, with Value after the change = 96, Percentage change = 20 %, original value = 80.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (original value, value after the change, percentage change) and fill in the others: it rearranges the formula for you.
