What is (x) After Going Up or Down by (p)%? — New Value Calculator
Use this calculator to find the new value of a number after applying a percentage increase or decrease. Useful for markups, markdowns, inflation, salary changes, investment returns, and more.
How does this calculation work?
When a value increases or decreases by a percentage, you are scaling it by a factor. A 20% increase means you end up with 120% of the original. A 20% decrease means you end up with 80%. This calculator applies that scaling in one step.
Formulas
Where x is the original value and p is the percentage change.
Step-by-step examples
Increase: What is 250 after a 12% increase?
- Factor = 1 + 12 ÷ 100 = 1.12
- 250 × 1.12 = 280
Decrease: What is 250 after a 12% decrease?
- Factor = 1 − 12 ÷ 100 = 0.88
- 250 × 0.88 = 220
Common real-world uses
| Scenario | Calculation | Result |
|---|---|---|
| $200 item with 30% discount | 200 × 0.70 | $140 |
| $50,000 salary + 8% raise | 50,000 × 1.08 | $54,000 |
| 1,000 units, 5% growth | 1,000 × 1.05 | 1,050 units |
| $3,000 rent, 3% increase | 3,000 × 1.03 | $3,090 |
| $500 product, 15% markup | 500 × 1.15 | $575 |
Frequently asked questions
Is a 50% decrease the same as a 50% increase reversed?
No. If you increase by 50% and then decrease by 50%, you do not return to the original. Example: 100 → +50% → 150 → −50% → 75. The base changes each time.
What if p is greater than 100% decrease?
A decrease greater than 100% would result in a negative value. In most real-world contexts a 100% decrease means the value reaches zero.
How do I apply multiple percentage changes?
Multiply the factors sequentially. For a 10% increase then a 5% decrease: x × 1.10 × 0.95. Do not add or subtract percentages directly.