Percentage Decrease Calculator
Percentage decrease measures how much a value shrank relative to where it started — price drops, weight loss, falling traffic. As with increases, the original value is the base, which is why the percentage down is not the mirror image of the percentage back up.
The formula
Decrease % = ((Old − New) ÷ Old) × 100
How to calculate it
- Subtract the new value from the old value to get the drop.
- Divide the drop by the old value (the starting point).
- Multiply by 100 to express it as a percentage.
Worked example
A price falls from 250 to 175. (250 − 175) ÷ 250 × 100 = 30% decrease.
Quick reference table
| From | To | Decrease |
|---|---|---|
| 100 | 80 | 20% |
| 60 | 45 | 25% |
| 250 | 175 | 30% |
| 500 | 450 | 10% |
| 40 | 30 | 25% |
| 90 | 45 | 50% |
Related percentage calculators
- What Is X Percent of Y?
- Percentage Increase Calculator
- X Is What Percent of Y?
- Percent Off Calculator (Discounts)
Or use the general percentage calculator for all three percentage questions in one place.
Frequently asked questions
What is the percentage decrease formula?
Subtract the new value from the old value, divide by the old value, and multiply by 100: ((Old − New) ÷ Old) × 100.
Can a decrease be more than 100%?
Only if the value goes negative. Falling to zero is exactly a 100% decrease, so for prices, weights and counts — which stop at zero — 100% is the practical maximum.
If something drops 20%, does a 20% rise restore it?
No. 100 down 20% is 80, but 80 up 20% is only 96. The percentages use different bases, so you'd need a 25% rise to get back to 100.