Question 1

How do I calculate percentage decrease?

Accepted Answer

Decrease = (Old - New) / Old × 100. From 100 to 75: (100-75)/100 × 100 = 25% decrease.

Question 2

What is 100 after a 30% decrease?

Accepted Answer

100 × (1 - 0.30) = 70. Or: 100 - 30 = 70. A 30% decrease leaves 70% of the original.

Question 3

How accurate are these calculations?

Accepted Answer

Our calculator uses double-precision floating-point arithmetic, accurate to about 15-16 significant digits for most calculations.

Question 4

Can I use the result in further calculations?

Accepted Answer

Yes, results are calculated to full precision. You can copy the exact value or use the rounded display depending on your needs.

Percentage Decrease Calculator

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