Percentage Decrease Calculator
Enter the original value and the new, lower value to find the percentage it fell by. Useful for measuring price cuts, revenue drops, weight loss, reduced costs, or any time a number has gone down and you need to express the change as a percentage. Worth noting: a 50% decrease followed by a 50% increase does not return to the original value — it lands at 75%.
When to use this calculator
Use this when a value has gone down and you need to quantify the drop — for example, a product price falling from $180 to $135, headcount reducing from 40 to 32, or website traffic dropping from 12,000 to 9,000 visits.
Percentage Decrease
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Results are instant — nothing is stored and no account is needed.
Related Calculators
How to Calculate
- Enter the original (starting) value in the first field.
- Enter the new (lower) value in the second field.
- The percentage decrease is shown instantly.
Formula
Subtract the new value from the original to get the drop. Divide by the original value, then multiply by 100. The result is always expressed as a positive percentage.
Examples
From 80 to 60
25% decrease
From 1000 to 750
25% decrease
From 45 to 27
40% decrease
Use Cases
- Measuring a price reduction on a product
- Tracking weight loss as a percentage of starting weight
- Reporting a drop in revenue or website traffic
- Calculating the size of a budget cut
- Measuring an energy or emissions reduction
FAQ
What is the percentage decrease from 100 to 80?
The percentage decrease from 100 to 80 is 20%. Calculation: ((100 − 80) / 100) × 100 = 20.
What is the percentage decrease from 200 to 130?
The percentage decrease from 200 to 130 is 35%. Calculation: ((200 − 130) / 200) × 100 = 35.
What is the percentage decrease from 500 to 400?
The percentage decrease from 500 to 400 is 20%. This comes up in pricing — if a product drops from £500 to £400, that's a 20% price cut.
Is a 50% decrease the same as halving a value?
Yes. A 50% decrease produces exactly half the original. Important to remember: a 50% decrease followed by a 50% increase does not return to the original — it results in 75% of the starting value.
What if my new value is higher than the original?
The result will be negative — meaning the value actually went up, not down. Use the percentage increase calculator if you're measuring growth.
How does this differ from a sale discount?
A percentage decrease tells you by how much a value fell. A discount expresses that same drop as a saving on a price. The maths is identical — if you want to calculate the final price after a percentage off, the discount calculator shows both the saving and the sale price in one step.