PercentSwift

Percentage point calculator

Enter an old rate and a new rate. You'll get the change in percentage points and the relative change in percent. Both are correct, and the page explains when to use each.

Percentage points vs percent change

Settings
%
%

Change in percentage points

+2 pp

4% to 6% is a change of +2 percentage points, or a 50% relative increase.

Relative change
+50%

Formula

Points = New rate − Old rate; Relative % = Points ÷ Old rate × 100

Steps

  1. Percentage points: 6 − 4 = +2 pp
  2. Relative change: 2 ÷ 4 × 100 = +50%
  • Both answers are correct. They describe the same change in different units, so say which one you mean.

Exact decimal arithmetic, calculated in your browser.

Examples

Each one loads into the calculator above.

Two ways to describe one change

When an interest rate goes from 4% to 6%, it has risen by 2 percentage points. It has also risen by 50%, because 2 is half of 4. Both statements are true. The first describes the gap between the two rates; the second compares that gap with where the rate started.

Saying a rate “rose 2%” is ambiguous. Readers might think it went from 4% to 4.08%. Use “percentage points” (or “pp”) for the subtraction and “percent” only for the relative change.

Which one should you report?

Report percentage points when the rates themselves are what readers care about: interest rates, unemployment, vote shares, conversion rates, test pass rates. Report the relative change when you want to show how big a shift is compared with the starting level, for example a conversion rate going from 2.1% to 2.8%, which is 0.7 points but a third more sales from the same traffic.

Relative changes of small rates can sound dramatic. A risk that goes from 0.2% to 0.3% has grown 50%, yet only 1 person in 1,000 is affected by the difference. Giving both numbers is often the honest choice.

Basis points

In finance, a basis point is one hundredth of a percentage point. A move from 5.25% to 5.5% is 0.25 percentage points, or 25 basis points.

Questions people ask

Guides that use this calculator