Z-score Calculator

Single value • Sample mean • Percentile ⇄ Z • Ajax loading • Hard reset

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🧮 Calculation type

Quick summary

Pick a mode and enter values.

📌 Inputs (single value)

Uses population standard deviation σ (must be > 0).

Z-score

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Percentile (Φ(z))

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As a percentage of the standard normal CDF.

Tail probabilities

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Left tail Φ(z) / Right tail 1−Φ(z)

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