Z score calculator

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Calculate z-scores online with ease

Transform your data into standardized z-scores to understand how far each value deviates from the mean. Perfect for comparing values from different distributions, identifying outliers, and understanding data distribution.

Analyze csv, parquet, tsv and json in seconds

Calculate z-scores using sample or custom parameters

Visualize z-score distribution

Identify outliers and extreme values

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Get instant insights about your data's standardized values

How to calculate z-scores online

  1. Upload your data
    Use the input box at the top of the page to upload your dataset
  2. Select a column
    Choose the numerical column you want to analyze
  3. Optional: Customize parameters
    Optionally enter custom mean and standard deviation values
  4. View z-scores
    See the calculated z-scores and their distribution
  5. Interpret results
    Use the interpretation guide to understand what the z-scores mean

Example distributions and their z-scores

Normal Distribution Z-Scores

A normal distribution's z-scores follow a standard normal distribution with mean 0 and standard deviation 1.

Sample Statistics:

  • Original mean: 9.99
  • Original standard deviation: 0.99
  • Z-scores mean: -0.00
  • Z-scores standard deviation: 1.00
MT cars
Motor Trends Car Road Tests dataset.
Rows: 32
Flights 1m
1 Million flights including arrival and departure delays.
Rows: 1,000,000
Iris
Iris plant species data set.
Rows: 50
House price
Housing price dataset.
Rows: 545
Weather
Weather dataset with temperature, rainfall, sunshine and wind measurements.
Rows: 366