From 80 to 150
Original 80.00, new value 150.00.
87.50% increase. Difference 70.00.
Percentage increase and decrease calculator
Compare an original number with a new one, or apply a percent increase or decrease. The baseline is always the original value.
Percent change
87.50%
Increase
- Difference
- 70.00
- Baseline
- 80.00
Original80.00
New value150.00
Next: Tip calculatorApply a percent to a bill.
Percent change is relative to the original value, using its absolute value as the baseline.
How this is calculated
- Step 1
Two numbers
Change mode compares the next value with the original.
- Step 2
Or a percent
Apply mode raises or lowers a base by the percent you type.
- Step 3
The sign
A fall is negative. A zero original cannot be a percent change.
Change from a baseline, or a percent applied to one number
change = (new − original) ÷ |original| × 100
| original | The baseline. A change from zero is undefined. |
|---|---|
| new | The value you compare with the baseline. |
| p | In apply mode, the percent you add or subtract. |
A move from 80 to 100 is 25%, because the change is measured against 80. It is not 20%.
Apply mode multiplies by 1 + p/100 for an increase and by 1 − p/100 for a decrease. Subtracting the percent from the number itself is a different operation.
A tip is this apply mode on a bill, plus a split. That lives on the tip calculator. A rate that compounds every month is not a one-time percent — use compound interest for that.
Worked examples
Loading an example fills the tool and scrolls you back to the result. Money examples stay in US dollars on the page. The symbol you picked changes; the numbers do not convert.
From 200 down to 150
Original 200.00, new value 150.00.
−25.00% decrease. Difference −50.00.
Raise 240 by 15%
Increase 240.00 by 15%.
Result 276.00. The change is 36.00.
Lower 80 by 25%
Decrease 80.00 by 25%.
Result 60.00. The change is −20.00.
Embed this calculator
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<iframe src="/embed/percentage-change" title="Percentage calculator" width="100%" height="720" style="border:0;max-width:42rem" loading="lazy"></iframe>Questions
Which number is the baseline?
The original. Percent change is (new − original) divided by the absolute value of the original. From 80 to 100 is 25%, not 20%.
What if the original number is zero?
The percent is undefined. Growing from nothing is not a percentage change. The tool says so instead of showing a fake number.
What about a negative original?
The denominator uses the absolute value, so the sign of the result still tells you whether the new number is higher or lower. A change from −80 to −60 is an increase.
Is a 15% decrease the same as subtracting 15?
No. A 15% decrease multiplies by 0.85. Subtracting 15 only matches that when the original number is 100.