Reverse Percentage
Recover the original amount before a known percentage increase or decrease. Use a negative percentage for a reduction.
How to use Reverse Percentage
- Enter “Final amount”, using the units and limits shown in its label.
- Enter “Applied change (%)”, using the units and limits shown in its label.
- Select Calculate or Process. Review the result and any validation message before copying or downloading available output. Reset clears the result and restores the starting inputs.
Method & assumptions
Original = final ÷ (1 + change ÷ 100).
Worked example
A final amount of 120 after a 20% increase started at 100.
Results and projections are informational estimates, not financial, medical, legal, tax, or property advice. Check assumptions, units, rounding, and local requirements independently. Investment illustrations do not guarantee returns. Keep original files and check transformed output before use.
Questions, answered
How do I reverse a discount?
Enter a negative change, such as −20 for a 20% discount. A 100% reduction cannot be reversed uniquely.
Where does this calculation run?
It runs locally in your browser. Enter plain numbers without currency symbols or thousands separators; use the same currency and measurement units throughout unless a converter explicitly asks for units.