What is a Z-score used for?

Z-scores allow you to compare data from different measurement scales (e.g., comparing an SAT score to an ACT score) by normalizing them to a common scale.

How do I interpret a Z-score of zero?

A Z-score of zero means your raw score is exactly equal to the mean (average).

What is an 'Outlier' in terms of Z-score?

Typically, any Z-score greater than +3 or less than -3 is considered an extreme outlier, as it is very far from the group average.

Why is 'Standardization' useful?

Standardization allows us to calculate probabilities (using a Z-table) and identify how unusual a specific data point is relative to its population.

Can Z-scores be negative?

Yes. A negative Z-score simply means the value is below the mean (the group average).

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IPL 2026

Z-score Calculator

Calculate standard scores to compare different datasets. Normalize values and identify outliers using the standard normal distribution.

Complete User Guide

Standardize your score with these steps:

Step 1: Enter the raw score (your data point).

Step 2: Enter the mean and standard deviation of the population.

Step 3: Click 'Calculate' to find the Z-score.

Step 4: Interpret the result. A Z-score of +1 means your value is 1 standard deviation above average.

The Mathematical Formula

Z = (x - μ) / σ

The Z-score (standard score) is the number of standard deviations a data point is from the mean:

- **Formula**: Z = (x - μ) / σ - **x**: Raw score - **μ**: Mean - **σ**: Standard Deviation

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