Descriptive Statistics Calculator

The Mean is the calculated average of a dataset (the sum of all numbers divided by the count of numbers). The Median is the middle value of a sorted dataset (or the average of the two middle values if the count is even). The Mode is the value that appears most frequently in the dataset (a dataset can be trimodal or multimodal if there are multiple values with the same highest frequency).

Standard Deviation is a metric of statistical dispersion. It quantifies how much the individual values in a dataset deviate from the mean. A low standard deviation shows that the data points tend to be close to the mean, while a high standard deviation indicates that the data points are spread out over a wider range.

Use Population Standard Deviation when you have gathered data from every single member of the group you are studying. Use Sample Standard Deviation when your dataset is a smaller sample taken from a larger population. The sample version divides by N - 1 instead of N (Bessel's correction) to correct for bias in estimating the population variance.

The Interquartile Range (IQR) measures the statistical spread of the middle 50% of your dataset. It is calculated as the difference between the third quartile (Q3, the 75th percentile) and the first quartile (Q1, the 25th percentile). Any data point that falls below Q1 - 1.5 × IQR or above Q3 + 1.5 × IQR is classified as an outlier. Unlike standard deviation, the IQR is highly resistant to outliers.

Because calculations and rendering run entirely client-side using highly optimized JavaScript algorithms directly in your browser, the calculator can easily parse, sort, and analyze datasets containing 50,000+ data points instantly without any server latency or upload limits.