Calculate mean, median, mode, standard deviation and more
Solution Steps
Pro featuresum = Σxᵢ, n = countsum = 0 = 0, n = 1Add every value together and record the number of entries.
See the Full Step-by-Step Solution
See every calculation step with detailed formulas, substitutions, and explanations.
Upgrade to Pro: $7.99/moData Distribution
Frequency of values in the dataset
What This Means For You
Get a personalized explanation of these results — what they actually mean for your situation, and how small changes would affect them.
How it works
Takes a list of numbers and returns the standard descriptive summary: mean, median, mode, range and standard deviation. Mean and median answer different questions, and the gap between them is a quick read on whether the data is skewed.
Mean x̄ = Σx / n Median = middle value of the sorted list (average of the two middle values when n is even) σ = √( Σ(xᵢ − x̄)² / n ) (population) s = √( Σ(xᵢ − x̄)² / (n − 1) ) (sample)
ncount of valuesx̄arithmetic meanModemost frequent value; undefined when every value appears onceRangelargest value minus smallestσ, spopulation and sample standard deviation
- Sum = 136 over n = 7, so the mean is 136 / 7 = 19.43
- Already sorted; the 4th of 7 values is the median: 18
- 15 appears twice and every other value once, so the mode is 15
- Sum of squared deviations from the mean = 235.71
- Population: 235.71 / 7 = 33.67, so σ = 5.80
- Sample: 235.71 / 6 = 39.29, so s = 6.27
- This tool divides by n, giving the population standard deviation. If your numbers are a sample drawn from something larger, divide by n − 1 instead; on seven values that raises the figure by about 8%.
- Mean above median, as here, points to a right tail. The value 30 drags the average up while leaving the median untouched, which is exactly why median income gets reported rather than mean income.
- A dataset can have no mode, one mode, or several. Two distinct peaks usually means two populations got mixed together, and no single summary number will describe that honestly.
Related Tools
Most Searched Today
Frequently Asked Questions
Mean is the arithmetic average. Median is the middle value when data is sorted. Mode is the most frequently occurring value. Each describes the center of a dataset differently.
Use the median when data is skewed or contains outliers. For example, median household income is more representative than mean income because very high earners skew the average.
Standard deviation measures how spread out values are from the mean. A low standard deviation means data points cluster near the average; a high one means they are more dispersed.
Population statistics describe an entire group, while sample statistics estimate population parameters from a subset. Sample standard deviation divides by (n-1) instead of n to correct for bias.