Mean: The arithmetic average — the sum of all values divided by the count. Sensitive to outliers; a single extreme value can pull it significantly.
Median: The middle value when data is sorted. More robust to outliers than the mean, making it a better center measure for skewed data.
Standard Deviation: How spread out your data is around the mean. A small value means data points cluster tightly; a large value means wide dispersion.
IQR (Interquartile Range): The range of the middle 50% of your data (Q3 − Q1). Values beyond 1.5 × IQR from Q1 or Q3 are often flagged as outliers.
Mode: The most frequently occurring value(s). If every value appears once, there is no mode.
How This Calculator Works
You paste or type a list of numbers separated by commas or spaces. The tool parses them, sorts the set, and runs a single-pass descriptive statistics computation: sum and mean, sorted-order median, frequency-count mode, population variance and standard deviation, min/max range, and interpolated quartiles using the (n+1)-position method. All results update live as you type.
Quick Questions
Is this population or sample standard deviation?
This calculator uses population standard deviation (divides by n). For sample standard deviation (divides by n−1), multiply the variance by n/(n−1) and take the square root, or use a dedicated sample statistics tool.
How many numbers can I enter?
There's no fixed limit, but very large data sets (thousands of values) may cause a brief delay as the browser processes them. For most homework and quick-check purposes, performance is instant.
What separators can I use?
Commas, spaces, tabs, or newlines all work. The parser splits on any whitespace or comma and ignores empty entries, so "1, 2, 3" and "1 2 3" produce identical results.
Why does the mode say "No mode"?
If every value in your data set appears the same number of times (e.g., all unique), there is no mode. A mode only exists when at least one value appears more frequently than the others.