Calculate percentage change

Measure the percentage increase or decrease between an old value and a new value.

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ToolPercentage Change
Input
Output
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How it works

Change is new minus old, divided by the absolute old value, multiplied by 100. The sign supplies the increase or decrease label while the absolute denominator keeps a negative baseline’s magnitude readable.

  • The old value cannot be zero because no finite percentage denominator exists.
  • No time period or compounding interpretation is inferred.

Worked example

Revenue Growth
Calculate percentage change from 80000 to 95000
Input
											80000, 95000
Output
												18.75% increase (from 80000 to 95000)

When to use this

Dashboards compare monthly revenue, laboratory notes report shifts from a baseline, and price reviews quantify increases or decreases.

Edge cases

  • A change from −100 to −80 is reported as a 20% increase under the absolute-baseline convention.
  • An old value of zero is rejected rather than reported as an infinite percentage.
  • Only two numeric tokens separated by whitespace or commas are parsed.