How to decrease a number by a percentage
New value = Original × (1 − Percentage ÷ 100)
Example: decrease 2,400 by 25% → 2,400 × 0.75 = 1,800. The reduction is 2,400 × 25 ÷ 100 = 600.
How to find the percentage decrease
Percentage decrease = (Old − New) ÷ Old × 100
Example: weight going from 80 kg to 72 kg is (80 − 72) ÷ 80 × 100 = 10% less.
| Original | Decrease | New value |
|---|---|---|
| 100 | 10% | 90 |
| 500 | 20% | 400 |
| 1,500 | 35% | 975 |
| 60,000 | 5% | 57,000 |
Frequently asked questions
How do I calculate a percentage decrease?
Subtract the new value from the old value, divide by the old value and multiply by 100.
Can a decrease be more than 100%?
Not for quantities that can't go below zero. A 100% decrease takes a value to zero.
How is this different from a discount?
It's the same calculation. A 20% discount on ₹1,000 is a 20% decrease, giving ₹800.