Online Tool Store
Average Calculator
Paste a list of numbers to instantly get the mean, median, mode, range, and sum. Runs entirely in your browser — nothing is uploaded.
This works right here on your device — nothing gets sent out.
Example shown — separate numbers with commas, spaces, or new lines.
How it works
- Paste or type a list of numbers, separated by commas, spaces, or new lines.
- The mean, median, mode, sum, count, min, max, range, midrange, standard deviation, variance, quartiles, and outliers update as you type.
- Use Copy results to copy the summary as plain text.
- Use the result to check your own arithmetic or summarize a data set quickly.
The formulas
Mean is the sum of all values divided by how many there are:
Mean = (sum of all numbers) / (count of numbers)
Median is the middle value once the numbers are sorted — the average of the two middle values if the count is even.
Mode is the value (or values) that appear most often in the list.
Spread is measured from the mean. Variance averages the squared distances from it, and the standard deviation is its square root. Range is max − min and midrange is (min + max) / 2.
Population variance = Σ(x − mean)² / n
Sample variance = Σ(x − mean)² / (n − 1)
IQR = Q3 − Q1, outlier if below Q1 − 1.5 × IQR or above Q3 + 1.5 × IQR
Example: for 4, 8, 6, 5, 3, 8, 9, 8, 2 — the mean is (4+8+6+5+3+8+9+8+2)/9 ≈ 5.89, the median (sorted: 2, 3, 4, 5, 6, 8, 8, 8, 9) is 6, and the mode is 8, since it appears three times. The sample standard deviation is about 2.52 and the population standard deviation about 2.38.
FAQ
What counts as a valid number list?
Any numbers separated by commas, spaces, or new lines — including negatives, decimals, and scientific notation such as 3e2, e.g. "4, -8.5, 6". Anything that is not a plain number (stray letters, Infinity, hex like 0x10) shows an error instead of silently being dropped or misread.
What does it do when there are multiple modes?
It lists every value that shares the highest frequency. If every number appears exactly once, there is no meaningful mode, so it shows "None" rather than an arbitrary pick.
How is the median calculated for an even-sized list?
The list is sorted, then for an even count the median is the average of the two middle values; for an odd count it is the single middle value.
What is the difference between sample and population standard deviation?
Population standard deviation divides the squared distances from the mean by n and is used when your list is the whole group. Sample standard deviation divides by n − 1 and is used when your list is a sample drawn from a larger group. With a single number the sample versions are undefined, so they show a dash.
How are the quartiles and outliers calculated?
Quartiles use linear interpolation between ranks — the same method as Excel QUARTILE.INC, Google Sheets and the NumPy and R defaults. The interquartile range (IQR) is Q3 − Q1, and a value is flagged as an outlier if it lies below Q1 − 1.5 × IQR or above Q3 + 1.5 × IQR. Other textbooks split the data into halves instead, which can give slightly different quartiles on small lists.
What is the range and the midrange?
The range is the maximum minus the minimum, so it measures the spread of the list. The midrange is the value exactly halfway between the minimum and the maximum: (min + max) ÷ 2.
Is my data uploaded anywhere?
No. Every calculation runs with plain JavaScript in your browser — the numbers you type never leave your device.
How we compare
| Feature | Online Tool Store | Omni Calculator | Pearson | CalculatorSoup |
|---|---|---|---|---|
| Range and midrange | ✓ | Range and midrange | Not listed | Range listed; midrange not listed |
| Sample and population standard deviation and variance | ✓ | Std dev and variance | Sample or population | Not listed |
| Quartiles, IQR and outliers | ✓ | Quartiles | Outliers by the IQR method | Quartiles, IQR and outliers |
| Copy the results | ✓ | Not listed | Not listed | Not listed |
| Paste from spreadsheets, any separator | ✓ | Enter up to 30 numbers | Commas, spaces, tabs or lines | Commas, spaces or lines |
Omni Calculator, Pearson and CalculatorSoup all cover mean, median and mode. Pearson also handles frequency tables and step-by-step working, and Omni Calculator shows the steps, which this tool doesn't. Choose this Average Calculator for a quick list of any size with the spread, quartiles and outliers alongside, and a one-click copy of the results.