Percentage Increase vs. Percentage Points

People often treat “percent” and “percentage points” as if they were the same thing. They are not. A change from 4% to 6% is an increase of 2 percentage points. Relative to the starting rate of 4%, it is also a 50% increase. Both statements can be true, and they answer different questions.

Mixing the two is one of the easiest ways to overstate or understate a change, especially in interest rates, election polls, tax rates, and exam pass rates. This article shows both formulas, works through examples, and explains when each figure is the one to report. For a single increase from any original value to a new value, you can also use the percentage increase calculator.

Two different measurements

A percentage point is the simple difference between two percentages. If a rate goes from A% to B%, the change in percentage points is B − A. No division is involved.

A percentage increase (or percentage change) is a relative change. It uses the starting value as the base:

When the values themselves are already percentages, the same formula applies: ((6 − 4) ÷ 4) × 100 = 50%. The 50% is a relative change in the rate. The 2 percentage points are the gap between the two rates.

A percentage *decrease* uses the same idea with the direction reversed, or you can keep the signed change and read a negative result as a decrease. The percentage decrease calculator and the percentage change calculator are both built for that arithmetic.

Example: an interest rate from 4% to 6%

Suppose an annual interest rate moves from 4% to 6%.

• Change in percentage points: 6 − 4 = 2 percentage points.
• Percentage increase: ((6 − 4) ÷ 4) × 100 = (2 ÷ 4) × 100 = 50%.

Saying “the rate increased by 50%” is correct if you mean a relative increase from 4%. Saying “the rate increased by 50 percentage points” would be wrong: that would be a jump from 4% to 54%. Saying “the rate increased by 2%” is also misleading, because 2% of 4% would be a much smaller move (to 4.08%). The accurate plain-language options are “rose by 2 percentage points” or “rose by 50% from 4% to 6%.”

Example: an exam score from 70% to 84%

A student’s overall score goes from 70% to 84%.

• Percentage points: 84 − 70 = 14 percentage points.
• Percentage increase: ((84 − 70) ÷ 70) × 100 = (14 ÷ 70) × 100 = 20%.

The student gained 14 percentage points, which is a 20% increase relative to the earlier score. If you only quote “a 20% increase,” a reader might imagine a climb all the way to 84% + 20 percentage points, or to 70% × 1.20 in a different context. Naming both the point change and the starting score keeps the meaning stable.

Example: a rate from 20% to 30%

• Percentage points: 30 − 20 = 10 percentage points.
• Percentage increase: ((30 − 20) ÷ 20) × 100 = 50%.

The relative increase is again 50%, even though the point change (10) is larger than in the 4%-to-6% case (2). That is the point of a relative measure: the same 50% means “half as large again as the start,” whatever the start was. The point change simply subtracts the two percentages and does not know whether you began at 4% or at 20%.

Why the starting value matters so much

Relative change divides by the original value. A small starting percentage makes a modest point change look like a large percentage increase. A move from 1% to 2% is only 1 percentage point, but it is a 100% increase. A move from 50% to 51% is also 1 percentage point, but it is only a 2% increase.

Neither figure is “more true” than the other. They are answers to different questions:

• Use percentage points when you want the gap between two rates that are already on a 0–100 scale, and you want every point to count the same.
• Use a percentage increase when you want to know how large the change is compared with where you started.

In public discussion, writers sometimes pick the figure that sounds more dramatic. If a rate doubles from 1% to 2%, “up 100%” and “up 1 percentage point” are both accurate; reporting only one of them can leave a misleading impression. The careful habit is to report the old value, the new value, and then the change, with the unit named as points or as a relative percent.

Percentage points are not only for percentages written with a % sign

The same distinction appears whenever a figure is already a rate. A tax of 5% that becomes 7% has risen by 2 percentage points, or by 40% relative to 5%. A poll moving from 48% to 51% has moved 3 percentage points, which is a 6.25% relative increase (3 ÷ 48 × 100 = 6.25%).

You can also apply the increase formula to ordinary numbers that are not percentages: a price from 50 to 80 is a 60% increase, because ((80 − 50) ÷ 50) × 100 = 60%. There is no “percentage point” reading in that case, because 50 and 80 are not themselves percentages. Percentage points enter the picture only when you are subtracting two percentages (or two rates expressed as percentages).

What not to do

• Do not call a point change a “% increase” without checking the base. A rise from 10% to 12% is 2 percentage points, and a 20% increase, not a 2% increase.
• Do not use the new value as the base if you mean a percentage increase from the start. ((6 − 4) ÷ 6) × 100 is about 33.33%, which is a different question.
• Do not compute a percentage increase from a starting value of 0. If a rate goes from 0% to 5%, the point change is 5 percentage points, but a relative increase is undefined, because you cannot divide by zero. Describe the new rate, or use points, rather than inventing a relative percentage.
• Do not average two percentage-point changes and assume they behave like one relative change. Successive relative changes compound; see Compound percentage change explained.

How this differs from percentage difference

Percentage difference compares two values using their midpoint, not the earlier value, as the base. It is symmetric: the result is the same whichever value you enter first. Percentage increase is not symmetric, and percentage points are just a subtraction. If you are not treating one value as the original, the percentage difference calculator is the better tool.

When to use each one

• Reporting a policy rate, a tax, or a poll: usually percentage points, plus the two rates.
• Reporting growth from a known baseline (sales, traffic, a previous score): a percentage increase or decrease.
• Comparing two measurements when neither is a natural start: percentage difference, or a plain difference in the original units.

If you are unsure, give the two raw figures first. Anyone can then compute both the point change and the relative change, and nobody has to guess which base you used.

Frequently asked questions