Percentage Decrease Calculator
Decrease a number by a percentage, optionally repeatedly, and see the increase needed to get back to the start.
Your inputs
Results
Decreased value
220
- Amount removed
- 30
- Total decrease
- 12%
- Increase needed to get back
- 13.636364%
✓Exact calculation — rounded only for display
What this calculator does
Apply a cut or discount and see how far you would need to rise to recover.
Formula and method
Result = value × (1 − p)^times; Recovery = 1 ÷ (1 − p)^times − 1
Worked example
Calculated by this tool with its default inputs:
Inputs
- Starting value: 250
- Decrease: 12 %
- Apply the decrease this many times (compounded): 1
Results
- Decreased value: 220
- Amount removed: 30
- Total decrease: 12%
- Increase needed to get back: 13.636364%
How to read the results
A 50 % fall needs a 100 % rise to recover — losses and gains are not symmetrical.
Assumptions and limitations
- A decrease of 100 % leaves zero and cannot be recovered by percentage growth.
Questions
Is 20 % off then 20 % off the same as 40 % off?
No — it is 36 % off, because the second cut applies to the already-reduced value.
Methodology and verification
- Result type
- Exact mathematical calculation (rounded only for display)
- Formula version
- 1.0
- Automated verification
- 3 reference and validation test cases, checked against independently computed values. The site cannot be built if any of them fail.
- Editorial review
- Awaiting human editorial review. The explanation was drafted with AI assistance; the formula and examples are verified by the automated tests above.
Privacy
Everything you enter is calculated in this browser and is not sent to Numerith or anyone else. Inputs are added to a share link only if you choose to include them. Privacy policy