Percentage Increase Calculator

Enter the original and new values to see the percentage increase between them.

Measuring growth correctly

Percentage increase measures how much a value has grown relative to where it started. The starting value is always the base, which is why the same absolute jump can be a large percentage from a small base and a tiny percentage from a large one.

This matters when comparing growth across very different sizes. A company adding ten thousand customers to a base of twenty thousand grew fifty percent, while the same ten thousand added to two million is a rounding error, even though the raw number is identical.

If the new value is smaller than the original, the calculator will report a negative percentage, which simply means the value fell rather than rose.

The formula

increase % = ( (new - old) / |old| ) x 100

Worked example

From 50 to 65: ((65 - 50) / 50) x 100 = +30%.

How to read your result

A positive result is an increase; a negative result means the value actually fell. The size of the change in units is shown below the percentage.

Frequently asked questions

What if the new value is smaller?: You will get a negative percent, which is a decrease - use the Percentage Decrease Calculator for clarity.
Is increase symmetric with decrease?: No. Going up 50% then down 50% does not return to the original value.
What base does the percentage use?: The original (old) value is always the base.

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