Average Percentage Calculator

How it works

To find the average of a set of percentages, add them all together and divide by how many values there are. This is the arithmetic mean, the same method used for finding the average of any set of numbers.

The formula

Why this works: Percentages are ordinary numbers on a scale of 0 to 100, so averaging them uses exactly the same arithmetic as averaging any other numbers. Adding all values and dividing by the count gives the central tendency of the group, which is what the average represents.

Worked examples

When to use this

Averaging percentages is useful whenever you want a single summary figure across several readings of the same type:

• Academic results across subjects: A pupil scores 74%, 68%, 81%, and 77% in four end-of-term tests. The average is 75%, giving a clear overall picture of performance that a list of individual marks does not. Teachers use this to track whether a student is consistently above or below their target grade.
• Business performance metrics: A marketing team's email open rates for the past five campaigns are 22%, 19%, 24%, 21%, and 23%. The average of 21.8% becomes the baseline against which future campaigns are measured. Tracking the average month-on-month shows whether performance is improving or declining.
• Annual pay rise history: An employee received pay rises of 3%, 2.5%, 4%, and 2% over four years. The average annual rise is 2.875%, which can be compared directly against average CPI inflation over the same period to understand whether real pay has risen or fallen.
• Customer satisfaction scores: A retailer with six UK stores records Net Promoter Score percentages of 78%, 82%, 71%, 85%, 79%, and 80%. The chain average of 79.2% feeds into quarterly reporting and helps identify which stores are performing below the group mean.

Understanding the result

The arithmetic average of percentages is only a fair summary when each percentage is based on the same sample size. If one store surveyed 30 customers and another surveyed 300, treating both satisfaction percentages as equally weighted distorts the overall average in favour of the smaller group. In these cases, a weighted average is more appropriate: multiply each percentage by its sample size, sum the results, and divide by the total number of responses.

A simple average also treats positive and negative values symmetrically. In a growth context, averaging a 50% increase and a 50% decrease gives 0%, but the actual combined effect is a 25% net loss (100 grows to 150, then falls to 75). For compounding growth rates, a geometric mean is technically more accurate than the arithmetic mean this calculator provides. For most practical purposes, the arithmetic average is a reasonable and widely understood summary.

Related concepts

➡ Before averaging, you may want to check how each value changed between periods using the percentage change calculator, which shows the rate of movement between any two figures. ➡ If you only have two percentages to compare, the percentage difference calculator measures the gap between them relative to their midpoint. ➡ To build a set of percentages from raw test results, the test score percentage calculator turns each raw score into a percentage ready to average.

How to do this in Excel

Enter your percentage values in cells A1 to A5 (without the % symbol). The AVERAGE function adds all values and divides by the count automatically, handling blank cells correctly. For a weighted average where each percentage has a different sample size in column B, use =SUMPRODUCT(A1:A5,B1:B5)/SUM(B1:B5) instead.

How to do this without a calculator

Add all the percentage values together and divide by how many there are. For three scores of 72%, 68%, and 81%: add to get 221, then divide by 3 to get 73.67%. If the numbers are close together, a quick shortcut is to pick the middle value as an anchor, find how much each value differs from it, average those differences, and add the result to the anchor. For 72, 68, 81 with anchor 74: differences are -2, -6, +7, average difference is -1/3, so average is 74 - 0.33 = 73.67.

Common mistakes

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