Average Calculator

How to use the average calculator

1. Enter or paste your numbers. Separate them with commas, spaces or new lines. A column copied from a spreadsheet works as is. Anything that isn’t a number, such as a header or a dollar sign on its own, is skipped.
2. Add weights if the values don’t count equally. Enter one weight per number, in the same order: credit hours for grades, quantities for prices, or the number of people in each group. Leave the box empty for a plain average.
3. Compare the results. The mean, median and mode answer slightly different questions. When they disagree, the gap tells you something about your data.

The mean: add up and divide

The open textbook Prealgebra 2e from OpenStax (section 5.5) starts with five numbers: 8, 12, 15, 9 and 6 add to 50, and 50 ÷ 5 = 10 (Example 5.49). Example 5.50 averages the ages of a family at a birthday party: 16, 26, 53, 56, 65, 70, 93 and 97 add to 476, so the mean age is 476 ÷ 8 = 59.5. Example 5.51 averages four phone bills, $42.75, $50.12, $41.54 and $48.15, to $45.64.

The mean uses every value, which makes it the right choice when the total matters. If you know the average monthly bill, you know the yearly cost: 12 × $45.64 = $547.68. It also means a single extreme value can pull it a long way.

The median and the mode

Median. Sort the values and take the middle one. With an even count, average the two middle values. OpenStax Example 5.52 sorts 12, 13, 19, 9, 11, 15 and 18 into 9, 11, 12, 13, 15, 18, 19, so the median is 13. Example 5.53 has ten quiz scores (83, 79, 85, 86, 92, 100, 76, 90, 88, 64); the middle two after sorting are 85 and 86, so the median is 85.5. The mean of the same quizzes is 843 ÷ 10 = 84.3, pulled down by the 64.

Mode. The value that appears most often. In Example 5.54, the ages of 29 students in a college math class include seven 20s, more than any other age, so the mode is 20. A list can have two modes, or none at all if every value appears once. The mode is the only kind of average that works for categories, such as the most common shoe size sold.

Range. Largest minus smallest. For the quiz scores, 100 − 64 = 36. It is a rough measure of spread; the standard deviation calculator gives a better one.

Which average should you use?

The class ages in Example 5.54 show why the choice matters. The mode is 20, the median is 21, and the mean is 660 ÷ 29 = 22.8. A few older students (29, 30, 40 and 44) raise the mean, but they barely move the median.

• Use the mean when values are fairly balanced and you care about totals: average daily sales, average test score, average cost per item.
• Use the median when a few very large or very small values could distort the picture, such as home prices, incomes or wait times. It describes the typical case.
• Use the mode for the most common choice or category, or when the values are labels rather than measurements.

When the mean is well above the median, the data has a long tail to the high side. When it is well below, a few low values are dragging it down. Reporting both is often the most honest summary.

Weighted averages

Use a weighted mean when some values stand for more than others. If you bought 10 pounds of coffee at $2 a pound and 30 pounds at $3, the average price you paid is (10 × 2 + 30 × 3) ÷ 40 = 110 ÷ 40 = $2.75 a pound, not the $2.50 you would get by averaging the two prices.

GPA works the same way, with grade points as the values and credit hours as the weights; the college GPA calculator adds the letter-grade scale. A course grade built from categories, such as homework 20% and exams 50%, is also a weighted mean with the percentages as weights.

Two classic averaging mistakes

Averaging averages. One class of 20 students averages 80 and another of 30 students averages 90. The overall average is not 85. The total of all scores is 20 × 80 + 30 × 90 = 4,300, over 50 students, which is 86. Enter 80 and 90 as values with 20 and 30 as weights to get the right answer.

Averaging rates. Drive 60 miles at 60 mph and 60 miles back at 40 mph, and your average speed is not 50 mph. The trip takes 1 hour plus 1.5 hours for 120 miles, so you average 48 mph. Rates such as speed or price per unit should be averaged by dividing totals, not by averaging the rates themselves.

The same averages in a spreadsheet

In Excel, =AVERAGE(A2:A11) gives the mean, =MEDIAN(A2:A11) the median, and =MODE.SNGL(A2:A11) a single mode, while MODE.MULT lists ties. Google Sheets accepts the same AVERAGE, MEDIAN and SUMPRODUCT formulas. A weighted mean with values in A and weights in B is =SUMPRODUCT(A2:A11,B2:B11)/SUM(B2:B11). Pasting the same column here gives the same results, plus the sorted list for a quick visual check.

Dropping the lowest score and other trims

Some classes drop each student’s lowest quiz. For the ten OpenStax quiz scores, removing the 64 leaves 843 − 64 = 779 points over 9 quizzes, an average of 86.6 instead of 84.3. Delete the value from the list to see the effect. A trimmed mean, which drops the same share of values from both ends, is a middle ground between the mean and the median when a few extreme values are suspect but you still want to use most of the data. Say so when you report it, because a trimmed average is not comparable with an untrimmed one.

Sources & assumptions

How this calculator gets its numbers. Full method: our methodology.

• Mean = sum ÷ count; median = middle sorted value, or the mean of the two middle values; mode = most frequent value(s).
• If every value appears equally often, there is no mode.
• Weighted mean = Σ(value × weight) ÷ Σweight, used only when the weight count matches and the weights are non-negative.
• Text that isn’t a number is skipped; commas separate values.

Sources

1. OpenStax (Rice University), Prealgebra 2e, 5.5 Averages and Probability. Mean, median and mode with Examples 5.49–5.54: a mean of 10, a mean family age of 59.5, a mean phone bill of $45.64, medians of 13 and 85.5, and a mode of 20.

Last reviewed November 2, 2026. When the mean and median disagree, reporting both describes the data more fairly.