Percentage Change Calculator

Calculate the percentage change between an original value and a new value — works for both increases and decreases.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Enter an original value and a new value to calculate the percentage change between them — positive for an increase, negative for a decrease.
The starting value, before the change.
The value after the change.

Your result

50.00%

Percentage change

Change amount25

AI explanation

Formula

Change % = (New − Old) / |Old| × 100

Worked example

50 changes to 75

Worked example: 50 changes to 75
FieldValue
Original value50
New value75
Change amount25
Percentage change50

Assumptions

  • A positive result means an increase; a negative result means a decrease.
  • The original value cannot be zero (percentage change from zero is undefined).

Frequently asked questions

How do I calculate percentage change?

Subtract the original value from the new value, divide by the absolute value of the original value, then multiply by 100.

What's the difference between percentage change and percentage difference?

Percentage change treats one value as the "before" baseline (directional — it matters which value is old and which is new). Percentage difference is symmetric and treats both values equally, using their average as the base — use the Percentage Difference Calculator for that.

Why is my result negative?

A negative percentage change means the new value is lower than the original — a decrease. Use the Percentage Decrease Calculator if you specifically want to frame it that way.

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