Statistics Calculator
Free online statistics calculator. Calculate mean, median, mode, range, variance, standard deviation, z-scores, and quartiles for any dataset.
Calculate comprehensive statistical measures for your dataset including central tendency, dispersion, and z-scores.
What is Statistics?
Statistics is the science of collecting, analyzing, and interpreting data. Key statistical measures help us understand data distributions:
Measures of Central Tendency
These describe the center or typical value of a dataset:
- Mean: The arithmetic average of all values
- Median: The middle value when data is sorted
- Mode: The most frequently occurring value
Measures of Spread (Dispersion)
These describe how spread out the data is:
- Range: Difference between maximum and minimum values
- Variance: Average of squared differences from the mean
- Standard Deviation: Square root of variance, measures typical deviation
- Interquartile Range (IQR): Range of the middle 50% of data
Z-Score
The z-score indicates how many standard deviations a value is from the mean:
z = (x - μ) / σ
A z-score of 0 means the value equals the mean. Positive z-scores are above the mean, negative are below.
Applications of Statistics
Statistics is essential in many fields:
- Science: Experimental analysis and hypothesis testing
- Business: Market research and quality control
- Medicine: Clinical trials and epidemiology
- Social Sciences: Survey analysis and demographic studies
- Finance: Risk assessment and portfolio analysis