Statistics Calculator
A comprehensive reporting suite for your numerical data.
10.5, 20.2, 15.7, 10.5, 33.1
Statistics Calculator
Enter your data set and get a complete descriptive statistics report instantly — mean, median, mode, standard deviation, variance, quartiles, range, and more. Everything you need for data analysis in one place.
How to Use This Calculator
- Enter your data values separated by commas, spaces, or new lines.
- Click Calculate to get the full descriptive statistics summary.
Statistics Computed
- Count (n): Number of data points
- Sum: Total of all values
- Mean: Average (sum ÷ n)
- Median: Middle value when sorted
- Mode: Most frequently occurring value(s)
- Standard Deviation: Measure of spread
- Variance: SD squared
- Min / Max / Range: Extremes and span
- Quartiles (Q1, Q2, Q3): Data divided into four equal parts
- IQR: Interquartile range (Q3 − Q1)
Example Analysis
Data: 12, 15, 15, 18, 20, 22, 25, 30
- Mean: 157/8 = 19.625
- Median: (18+20)/2 = 19
- Mode: 15 (appears twice)
- SD (sample): ≈ 5.87
- Range: 30−12 = 18
- Q1: 15 | Q3: 23.5 | IQR: 8.5
Common Mistakes to Avoid
- Using mean for skewed data — Income data is skewed right; the mean is higher than most people earn. Use median for skewed distributions.
- Reporting mode when there is none or many — Data can be bimodal (two modes) or amodal (all values equal frequency). Know what you're reporting.
- Ignoring outliers — One extreme value can dramatically shift the mean. Check for outliers using IQR method: values below Q1−1.5×IQR or above Q3+1.5×IQR.
Frequently Asked Questions
When should I use mean vs. median?
Use mean for symmetric distributions without extreme outliers (height, test scores). Use median for skewed data or when outliers exist (income, home prices, response times).
What is the five-number summary?
Min, Q1, Median (Q2), Q3, Max. It's the basis of a box-and-whisker plot and gives a compact picture of data distribution, center, and spread.
What does IQR tell you?
The Interquartile Range is the range of the middle 50% of data. It's more robust than range for describing typical spread because it ignores the most extreme 25% on each end.
Conclusion
Descriptive statistics transform raw data into meaningful insights. Use this calculator for any data set — class grades, survey responses, measurements, or financial figures — and get the full picture instantly.
Related: Standard Deviation Calculator | Mean Median Mode Calculator | Z-Score Calculator
Data Tip
Standard deviation measures how much the values differ from the mean. A small standard deviation means the data is tightly clustered, while a large one means it is widely spread.
