Average Calculator
Paste or type a list of numbers to get the mean, median, mode and more, plus a separate weighted-average section.
Enter at least one number to see results.
Weighted average
Enter each value with its weight, for example grades and their percentages.
Formulas
Mean = (x₁ + x₂ + … + xₙ) / n
Median = middle value of the sorted list (average of the two middle values if n is even)
Mode = value(s) occurring most often (shown only when a value repeats)
Geometric mean = (x₁ · x₂ · … · xₙ)^(1/n), all xᵢ > 0
Harmonic mean = n / (1/x₁ + 1/x₂ + … + 1/xₙ), all xᵢ > 0
Weighted average = Σ(valueᵢ · weightᵢ) / Σ weightᵢ
Outlier fences = Q1 − 1.5 × IQR and Q3 + 1.5 × IQR, where IQR = Q3 − Q1
How it works
- Paste or type your numbers into the box, separated by commas, spaces or new lines.
- Read the mean, median, mode, geometric and harmonic mean, which update as you type.
- For a weighted average, add value and weight rows in the second section and copy the result.
Frequently asked questions
- What is the difference between mean, median and mode?
- The mean is the sum of all values divided by how many there are, the median is the middle value once the data is sorted, and the mode is the value that appears most often. The mean is sensitive to extreme values, while the median is robust against them, which is why house prices and salaries are usually reported as medians.
- How is a weighted average calculated?
- Each value is multiplied by its weight, those products are summed, and the total is divided by the sum of the weights. This is the standard method for course grades, GPA, portfolio returns and any situation where some entries count more than others.
- Why does the geometric or harmonic mean sometimes not appear?
- The geometric mean is only defined for strictly positive numbers, and the harmonic mean also requires all values to be positive. If your list contains a zero or a negative number, those two results are hidden rather than showing a misleading figure.
- Are my numbers uploaded anywhere?
- No. Every calculation runs in JavaScript inside your browser, and nothing is sent to a server. You can paste sensitive figures such as salaries or medical readings and they never leave your device.
- How does the outlier hint work?
- The tool computes the interquartile range (IQR) and flags values below Q1 − 1.5 × IQR or above Q3 + 1.5 × IQR, the same fence rule used in box plots. Flagged values are not removed automatically; the hint simply tells you which entries may be skewing the mean so you can decide whether to exclude them.
About this tool
This average calculator takes a list of numbers and instantly reports the arithmetic mean, median, mode, geometric mean and harmonic mean, along with the count, sum, minimum and maximum. You can separate values with commas, spaces, semicolons or line breaks — pasting a column straight from a spreadsheet works without any cleanup. Results update live as you type, and a sorted preview of your data lets you confirm the tool parsed exactly what you intended.
Everything runs client-side in your browser. The numbers you enter are parsed and averaged in JavaScript on your own device, with no network request and no server storage, so it is safe to use with grades, salaries, lab measurements or financial figures. The tool also computes quartiles and applies the standard 1.5 × IQR fence rule to point out possible outliers — useful because a single typo like a missing decimal point can drag the mean far from the true center of your data.
The separate weighted-average section handles the common case where entries do not count equally. Add a row per item with its value and weight — exam scores weighted by percentage, product ratings weighted by review count, or purchase prices weighted by quantity — and the weighted mean updates as you edit. Weights do not need to add up to 100; the calculator normalizes by the total weight automatically.
A few practical tips: use the median instead of the mean when your data contains extreme values, since one outlier can move the mean a long way. The geometric mean is the right choice for averaging growth rates or ratios, and the harmonic mean is correct for averaging rates such as speeds over equal distances. The formulas for every statistic are shown in the details block, so you can verify or reproduce any result by hand.